Let:
x = mL of soda solution
y = mL of syrup solution
The soda solution is 80% strength and the syrup solution is 0% strength, thus the combination of x and y of each solution gives strength of:
80x + 0y
This combination must be 60% strength, thus:
80x + 0y = 60(x + y) [1]
The total amount of solution is 65 mL, thus:
x + y = 65
Substituting in [1]
80x + 0y = 60*65
Operating and simpliifying:
80x = 3900
Dividing by 80:
x = 48.75
I need 48.75 mL of soda solution
calculate the length of side AC
Answer:
×=12+5
×=144+25
×=169
×=13
QUESTION 6 1 POINTA 20-foot string of lights will be attached to the top of a 12-foot pole for a holiday display. How far from the base of the poleshould the end of the string of lights be anchored?20 AProvide your answer below:ftFEEDBACK+O
EXPLANATION
Since we have the given sides, we can apply the Pythagorean Theorem in order to obtain the needed distance:
[tex]Hypotenuse^2=Larger\text{ side}^2+Smaller\text{ side}^2[/tex]Plugging in the terms into the expression:
[tex]20^2=Larger\text{ side\textasciicircum2+12}^2[/tex]Subtracting 12^2 to both sides:
[tex]20^2-12^2=Larger\text{ side}^2[/tex]Computing the powers:
[tex]400-144=Larger\text{ side}^2[/tex]Subtracting numbers:
[tex]256=Larger\text{ side}^2[/tex]Applying the square root to both sides:
[tex]\sqrt{256}=Larger\text{ side}[/tex]Computing the root:
[tex]16=Larger\text{ side}[/tex]Switching sides:
[tex]Larger\text{ side =16}[/tex]In conclusion, the solution is 16ft
AC⌢ =84 ∘ , find m∠ADC.
The measure of minor arc is 84 degree
The expression for the an angle inscribed in a circle, then the measurement of the angle is equal to the half of the measure of its intercepted arc.
[tex]\text{Angle}=\frac{1}{2}m(arc)[/tex]here we have, arc length = 84 degree
[tex]\begin{gathered} m\angle ADC=\frac{1}{2}(mAC) \\ m\angle ADC=\frac{1}{2}\times84 \\ m\angle ADC=42^o \end{gathered}[/tex]Angle = 42 degree
Question 4: -12a - 4 and -4(3a - 1) are equivalent expressions. True False > false
If we use the distributive property on the second expression, we get the following:
[tex]-4\cdot(3a-1)=-4\cdot(3a)-4(-1)=-12a+4[/tex]therefore, the expressions are not equivalent
*Identify the transformations for the function below. Check all that applyf(x) = -3x + 2DilationHorizontal ShiftVertical ShiftAReflection
f (x) = -3x + 2
then
Dilation is 3
Horizontal shift , find 0= -3x +2, x = 2/3
Vertical shift , x= 0 , y=+2
Reflection , find slope m' = -1/m = -1/-3= 1/3
I need the steps on how to go about this
Answer:
Explanation:
please let me know when I come to work with this
Comparing the blue bars (8 - 12 yrs old) and orange bars (13 - 17 yrs old), we can see that most of the blue bars centered between 1 - 1.9 hours of screen time while the orange bars somehow centered between 3 - 3.9 hours of screen time.
If more screen time mean less exercise, then, we can infer that on average, 13 to 17-year-olds gets less exercise compared to 8 to12-year-olds. (Option 3)
-82638•9390(69)+420 please help me with this
EXPLANATION
Given the operation -82638•9390(69)+420, multiplying numbers and applying the sign rule:
=-775970820(60) + 420
Applying the distributive property:
= -46558249200 + 420
Adding numbers:
= -46558248780
The solution is -46558248780
A clothing manufacturer has 1,000 yd. of cotton to make shirts and pajamas. A shirt requires 1 yd. of fabric, and a pair of pajamas requires 2 yd. of fabric. It takes 2 hr. to make a shirt and 3 hr. to make the pajamas, and there are 1,600 hr. available to make the clothing. i. What are the variables? ii. What are the constraints? iii. Write inequalities for the constraints. iv. Graph the inequalities and shade the solution set. v. What does the shaded region represent? vi. Suppose the manufacturer makes a profit of $10 on shirts and $18 on pajamas. How would it decide how many of each to make? vii. How many of each should the manufacturer make, assuming it will sell all the shirts and pajamas it makes?
Let the number of shirts is x and the number of pairs of pajamas is y
Then the variables are x and y which are the numbers of shirts and pajamas
Since each shirt needs, 1 yard and a pair of pajamas needs 2 yards
Since there are 1000 yards to make them
Then the first inequality is
[tex]\begin{gathered} (1)x+(2)y\leq1000 \\ x+2y\leq1000 \end{gathered}[/tex]Since the time to make a shirt is 2 hours and the time to make a pair of pajamas is 3 hours
Since there are 1600 hours available, then
The second inequality is
[tex]\begin{gathered} (2)x+(3)y\leq1600 \\ 2x+3y\leq1600 \end{gathered}[/tex]Then let us answer the questions
i. The variables are x and y
ii. The constraints are 1000, 1600
iii. The inequalities are
[tex]\begin{gathered} x+2y\leq1000 \\ 2x+3y\leq1600 \end{gathered}[/tex]iv. Let us draw the graph
The red area represents the 1st inequality
The blue area represents the 2nd inequality
The area of the two colors is the area of the solutions of the 2 inequalities
V.
The shaded region represents the solution of the 2 inequalities, the numbers of shirts and pajams
Vi.
The intersection point between the 2 lines is (200, 400)
Then we will take this point to represents the number of shirts and pajamas
vii.
Since the profit on shirts is $10 and on pajama is $18
Then we should make 200 shirts and 400 pajamas
Joshua has $1.20 worth of nickels and dimes. He has 6 more nickels than dimes.
Graphically solve a system of equations in order to determine the number of nickels,
x, and the number of dimes, y, that Joshua has.
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
0
Click twice to plot each line. Click a line to delete it.
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
Answer:
12 nickels, 6 dimes
Step-by-step explanation:
0.05x + 0.1y = 1.20
x - 6 = y
0.05x + 0.1(x-6) = 1.20
0.05x + 0.1x - 0.6 = 1.20
0.15x = 1.80
x = 12
(12) - 6 = y
y = 6
Now graph y = x - 6 and y = (-1/2)x + 12
If you don't know how to graph the functions, then go to khan academy for help.
Please help me to select the correct image for the representation of the function f(x) = 4 x3x?
Answer:
Explanation:
Given the below exponential function;
[tex]f(x)=4\cdot3^x[/tex]To be able to graph the above function, we'll go ahead and choose different values for x and determine the corresponding values of f(x).
When x = 0, we'll have;
[tex]f(0)=4\cdot3^0=4\cdot1=4[/tex]Looking at all the given four graphs, we can observe that only one of them has a y-interce
The formula for the volume of a rectangular prism is found by multiplying the width, length, and height of the prism. In other words, V = lwh. Solve the formula for the width, w.
The formula for the volume of a rectangular prism is
[tex]V=l\cdot h\cdot w[/tex]You need to write the formula for w, note that the width is being miltiplied by "lh"
to cancel this multiplication you have to divide it by "lh" and to keep the equality valid, what is done to one side of the expression must be done to the other, so divide V by "lh" too
[tex]w=\frac{V}{lh}[/tex]8. A farm water tower (with a capacity of 615 cubic metres) has sprung a leak. It loses water at the rate of 1 cubic metre an hour. If no one fixes it, when would the tower be empty? (Answer in weeks, days and hours; for example, 2 weeks, 2 days and 5 hours.)
Given: A farm water tower (with a capacity of 615 cubic metres) has sprung a leak. It loses water at the rate of 1 cubic metre an hour
Find: when would the tower be empty.
Explanation: A capacity of farm water tower is 615 cubic meters.
if it loses water at the rate of 1 cubic meter an hour
it means it take 615 hours to be empty.
[tex]615\text{ hours=}\frac{615}{24}=25.625\text{ days}[/tex]25.625 conatins 3 weeks= 21 days.
25.625-21=4.625 days.
4.625 days contains 4 days and
[tex]0.625\times24=15\text{ hours}[/tex]Hence the final answer will be 3 weeks, 4 days and 15 hours .
please see the picture below. I'll only need b c and d
Given:
• cotθ = -3
,• secθ < 0
,• 0 ≤ θ < 2π
Here the cot value of the angle is negative.
The cotangent function is negative in quadrants II and IV.
Also, secθ < 0, which means it is negative.
Secant function is negative in II and III quadrants.
Therefore, the angle will be in quadrant II.
Let's find the exact values of the following:
• (a). sin(2θ)
Apply the double angle formula:
[tex]sin(2\theta)=2sin\theta cos\theta=\frac{2tan\theta}{1+tan^2\theta}[/tex]Where:
[tex]tan\theta=\frac{1}{cot\theta}=-\frac{1}{3}[/tex]Thus, we have:
[tex]\begin{gathered} sin(2\theta)=\frac{2*(-\frac{1}{3})}{1+(-\frac{1}{3})^2} \\ \\ sin(2\theta)=\frac{-\frac{2}{3}}{1+\frac{1}{9}}=\frac{-\frac{2}{3}}{\frac{9+1}{9}}=\frac{-\frac{2}{3}}{\frac{10}{9}} \\ \\ sin(2\theta)=-\frac{2}{3}*\frac{9}{10} \\ \\ sin(2\theta)=-\frac{3}{5} \\ \\ \text{ Sine is positive in quadrant II:} \\ sin(2\theta)=\frac{3}{5} \end{gathered}[/tex]• cos(2θ):
Apply the formula:
[tex]cos(2\theta)=\frac{1-tan^2\theta}{1+tan^2\theta}[/tex]Thus, we have:
[tex]\begin{gathered} cos(2\theta)=\frac{1-(-\frac{1}{3})^2}{1+(-\frac{1}{3})^2} \\ \\ cos(2\theta)=\frac{1-\frac{1}{9}}{1+\frac{1}{9}} \\ \\ cos(2\theta)=\frac{\frac{9-1}{9}}{\frac{9+1}{9}}=\frac{\frac{8}{9}}{\frac{10}{9}}=\frac{8}{9}*\frac{9}{10}=\frac{4}{5} \\ \\ cos(2\theta)=\frac{4}{5} \\ \text{ } \\ \text{ Cosine is negative in quadrant II>} \\ cosine(2\theta)=-\frac{4}{5} \end{gathered}[/tex]• (c). sin(θ/2):
Apply the formula:
[tex]cos\theta=1-2sin^2(\frac{\theta}{2})[/tex]Where:
[tex]tan\theta=\frac{opposite}{adjacent}=-\frac{1}{3}[/tex]Now, let's find the hypotenuse using Pythagorean Theorem:
[tex]\sqrt{1^2+3^2}=\sqrt{1+9}=\sqrt{10}[/tex]Thus, we have:
[tex]cos\theta=\frac{adjacent}{hypotenuse}=-\frac{3}{\sqrt{10}}[/tex]Now, the function will be:
[tex]\begin{gathered} cos\theta=1-2sin^2(\frac{\theta}{2}) \\ \\ -\frac{3}{\sqrt{10}}=1-2sin^2(\frac{\theta}{2}) \\ \\ 2sin^2(\frac{\theta}{2})=1+\frac{3}{\sqrt{10}} \\ \\ 2sin^2(\frac{\theta}{2})=\frac{10+3\sqrt{10}}{10} \\ \\ sin^2(\frac{\theta}{2})=\frac{10+3\sqrt{10}}{20} \\ \\ sin(\frac{\theta}{2})=\sqrt{\frac{10+3\sqrt{10}}{20}} \end{gathered}[/tex]• (d). cos(,(θ/2)):
[tex]\begin{gathered} 2cos\theta=2cos^2(\frac{\theta}{2})-1 \\ \\ cos\frac{\theta}{2}=\sqrt{\frac{1+cos\theta}{2}}=\sqrt{\frac{1-\frac{3}{\sqrt{10}}}{2}} \end{gathered}[/tex]ANSWER:
[tex]\begin{gathered} (a).\text{ }\frac{3}{5} \\ \\ \\ (b).\text{ -}\frac{4}{5} \\ \\ \\ (c).\text{ }\sqrt{\frac{10+3\sqrt{10}}{20}} \\ \\ \\ (d).\text{ }\sqrt{\frac{1-\frac{3}{\sqrt{10}}}{2}} \end{gathered}[/tex]select the expression that will calculate how many eighths are in 2 bars
Answer:
Explanations:
Look for a pattern in the following list. Then use this pattern to predict thenext number. 2, -2, 3, -3, 4, ... *
Here, we are given the following numbers:
2, -2, 3, -3, 4.........
The pattern here is that a positive integer is followed by its negative value.
We can see that the number after 2 is its negative value -2
The number after 3 is its negative vaule -3
The number after 4 will be its negative which is -4
ANSWER:
-4
On a unit circle, ___ radians. Identify the terminal point andsin f.
Remember the following:
[tex]\begin{gathered} \sin(0)=0 \\ \\ \sin\left(\frac{\pi}{6}\right)=\frac{1}{2} \\ \\ \sin\left(\frac{\pi}{4}\right)=\frac{\sqrt{2}}{2} \\ \\ \sin\left(\frac{\pi}{3}\right)=\frac{\sqrt{3}}{2} \\ \\ \sin\left(\frac{\pi}{2}\right)=1 \end{gathered}[/tex][tex]\begin{gathered} \cos(0)=1 \\ \\ \cos\left(\frac{\pi}{6}\right)=\frac{\sqrt{3}}{2} \\ \\ \cos\left(\frac{\pi}{4}\right)=\frac{\sqrt{2}}{2} \\ \\ \cos\left(\frac{\pi}{3}\right)=\frac{1}{2} \\ \\ \cos\left(\frac{\pi}{2}\right)=0 \end{gathered}[/tex]The terminal point of an angle θ is given by:
[tex](\cos\theta,\sin\theta)[/tex]For θ=π/2, we have:
[tex](\cos\frac{\pi}{2},\sin\frac{\pi}{2})=(0,1)[/tex]Therefore, the answer is: option B) Terminal point: (0,1), sinθ=1.
simplify the following giving the answer with a positive exponent 2n^4*2n^3÷4
so the answer is n^7
The number line below represents which combined inequality? xs-6 orx 25 xs -6 and x 2 5 X2 -6 and x s 5 x2-6 or x s 5
Answer
Option C is correct.
x ≥ -6 and x ≤ 5
Explanation
In graphing inequality equations, the first thing to note is that whenever the equation to be graphed has (< or >), the circle at the beginning of the arrow is usually unshaded.
But whenever the inequality has either (≤ or ≥), the circle at the beginning of the arrow will be shaded.
Since the beginning of the blue mark is a shaded circle, the inequality is (≤ or ≥).
And considering that the region of the answer is between -6 and 5, it is evident that x is greater than or equal to -6 and less than or equal to 5. In mathematical terms,
x ≥ -6 and x ≤ 5
-6 ≤ x ≤ 5
Hope this Helps!!!
Solve the equation for y in terms of x. In other words, algebraicallyrearrange the equation so that the y variable is by itself one side of theequation. Type your answer in the form y = mx + b. If you have a valuethat is not an integer then type it rounded to the nearest hundredth. Donot put spaces between your characters.4x + 2y = 8y = ?
We can determine an expression of y in terms of x by isolating y on one side of the equation, we can do this by means of some algebraic operations to get:
4x + 2y = 8
1. Subtract 4x from both sides of the equation:
4x - 4x + 2y = 8 - 4x
0 + 2y = 8 - 4x
2y = 8 - 4x
2. Divide both sides by 2
2y/2 = (8 - 4x)/2
y = 4 - 2x
y = -2x + 4
Then, the equation of y in terms of x is y=-2x+4
Consider the line y=2x/3 - 7 Find the equation of the line that is perpendicular to this line and passes through the point (2, 6)Find the equation of the line that is parallel to this line and passes through the point (2, 6)Equation of perpendicular line: Equation of Parallel line:
The equation of a line in the slope intercept form is expressed as
y = mx + c
where
m = slope
c = y intercept
The given equation is
y = 2x/3 - 7
By comparing both equations,
m = 2/3
If two lines are perpendicular, it means that the slope of one line is equal to the negative reciprocal of the slope of the other line. This means that the slope of the perpendicular line passing through the point (2, 6) is the negative reciprocal of 2/3. It is - 3/2
Thus, m = - 3/2
We would find the y intercept of the perpendicular line by substituting m = - 3/2, x = 2 and y = 6 into the slope intercept equation. We have
6 = - 3/2 * 2 + c
6 = - 3 + c
c = 6 + 3 = 9
By substituting m = - 3/2 and c = 9 into the slope intercept equation, the equation of the perpendicular line is
y = - 3x/2 + 9
Also,
If two lines are parallel, it means that the slope of one line is equal to the slope of the other line. This means that the slope of the parallel line passing through the point (2, 6) is 2/3
Thus, m = 2/3
We would find the y intercept of the perpendicular line by substituting m = 2/3, x = 2 and y = 6 into the slope intercept equation. We have
6 = 2/3 * 2 + c
6 = 4/3 + c
c = 6 - 4/3 = 14/3
By substituting m = 2/3 and c = 14/3 into the slope intercept equation, the equation of the parallel line is
y = 2x/3 + 14/3
I need help with the question
B
For this problem Let's work in parts
1) Coin
Heads
Tails
Flipping the coin once, the Probability is:
[tex]P\text{ =}\frac{1}{2}[/tex]For there are two possible results, Heads or Tails, and there was one flipping.
2) Spinner
1 to 6 sections
The Probability of this spinner lands on a number lesser than 3
[tex]P\text{ =}\frac{2}{6}\text{ = }\frac{1}{3}[/tex]is 1 out of 3 for this spinner, since only 1, 2 are valid results.
So, the answer to this experiment
[tex]P\text{ = }\frac{1}{3}\cdot\frac{1}{2}\text{ = }\frac{1}{6}[/tex]Is the probability of both happen, both spinner and coin are 1 in six flipping. Since there are only two numbers < 3 on the spinner and two possibilities for the coin.
B
Heads, 1
Tails 1
Heads2
Tails 2
Solve equation 1/4 + 1/7=1/t for t to find the number of days it would take them to paint the house if they worked together. Number 361
ANSWER:
2.5 days.
STEP-BY-STEP EXPLANATION:
We have the following equation:
[tex]\frac{1}{4}+\frac{1}{7}=\frac{1}{t}[/tex]We solve for t:
[tex]\begin{gathered} \frac{1\cdot7+4\cdot1}{4\cdot7}=\frac{1}{t} \\ \frac{11}{28}=\frac{1}{t} \\ t=\frac{28}{11}\approx2.5\text{ days} \end{gathered}[/tex]Therefore, if they work together, they could paint the house in about 2.5 days.
Add.(7g + 4) + (8g + 2)
We have to add the expression.
We will group the similar terms:
[tex]\begin{gathered} \mleft(7g+4\mright)+(8g+2) \\ 7g+8g+4+2 \\ 15g+6 \end{gathered}[/tex]Answer: 15g+6
Solve for y:5x-8y=40
Solve for y means we need to isolate y from the equation:
We need to use inverse operations to solve equations:
[tex]\begin{gathered} 5x-8y=40 \\ -8y=40-5x \\ y=\frac{-5}{-8}x+\frac{40}{-8} \\ y=\frac{5}{8}x-5 \end{gathered}[/tex]Please see attachment for question.Fill in the table and then graph the function
ANSWER
EXPLANATION
First, we have to fill in the table. To do so, we will plug the x-values into the function to find the corresponding value of y,
[tex]\begin{cases}y=-3\cdot3^{-3}=-\frac{3}{3^3}=-\frac{3}{27}=-\frac{1}{9} \\ \\ y=-3\cdot3^{-2}=-\frac{3}{3^2^{}}=-\frac{3}{9}=-\frac{1}{3} \\ \\ y=-3\cdot3^{-1}=-\frac{3}{3^1}=-\frac{3}{3}=-1 \\ \\ y=-3\cdot3^0=-3\cdot1=-3 \\ \\ y=-3\cdot3^1=-3\cdot3=-9 \\ \\ y=-3\cdot3^2=-3\cdot9=-27 \\ \\ y=-3\cdot3^3=-3\cdot27=81\end{cases}[/tex]So, the table is,
Next, we have to graph all of these points in the coordinate plane. The last one cannot be graphed because y = -81 does not fit in the given coordinate plane. Also, the first two values won't be very accurate because of the scale of the y-axis. The graphed points are,
And finally, to graph the function we join the dots with a line.
Which exponential expressions are equivalent to the one below? Check allthat apply.(3.7) 10A. 310 + 710B. (3:7)10O .C. 2110O d. 310.710
Given the exponential expression:
[tex](3\cdot7)^{10}[/tex]The equivalent expressions are:
[tex]\begin{gathered} (3\cdot7)^{10}=3^{10}\cdot7^{10} \\ (3\cdot7)^{10}=21^{10} \end{gathered}[/tex]So, the answer will be options C, D
A phone company offers two monthly charge plans. In Plan A, the customer pays a monthly fee of $30 and then an additional 9 cents per minute of use. In PlanB, the customer pays a monthly fee of $33.60 and then an additional 8 cents per minute of use.For what amounts of monthly phone use will Plan A cost less than Plan B?Use m for the number of minutes of phone use, and solve your Inequality for m.
Let m denote the number of minutes.
Plan A:
The customer pays a monthly fee of $30 and then an additional 9 cents per minute of use.
Mathematically,
[tex]30+0.09m[/tex]Plan B:
The customer pays a monthly fee of $33.60 and then an additional 8 cents per minute of use.
Mathematically,
[tex]33.60+0.08m[/tex]For what amounts of monthly phone use will Plan A cost less than Plan B?
[tex]30+0.09m<33.60+0.08m[/tex]Let us solve the above inequality for m
[tex]\begin{gathered} 30+0.09m<33.60+0.08m \\ 0.09m-0.08m<33.60-30 \\ 0.01m<3.60 \\ m<\frac{3.60}{0.01} \\ m<360 \end{gathered}[/tex]This means that for less than 360 minutes, plan A will cost less than Plan B.
peter is paid k500.00 for the work in 18 hours. how much would he be paid if he had worked six hours
Given:
500 Kina for 18 hours of work
To determine the amount of payment if he had worked for 6 hours, we use ratio.
So,we let x be the amount of payment for 6 hours of work:
[tex]\begin{gathered} \frac{500\text{ Kina}}{18\text{ hours}}=\frac{x}{6\text{ hours}} \\ \text{Simplify and rearrange} \\ x=\frac{500(6)}{18} \\ \text{Calculate} \\ x=166.67\text{ Kina} \end{gathered}[/tex]Therefore, he would be paid 166.67 Kina if he had worked for six hours.
I am doing an equation trying to figure out a formula for the volume of a box and I am so lost I will include a picture
The volume of any rectangular box is expressed as:
[tex]\text{Volume}=\text{length}\times\text{breadth}\times height[/tex]Now, for the box that will be formed from the figure shown in the question, we will have:
length = 37 - 2x
breadth = 37 - 2x
height = x
Thus, we have that:
[tex]\begin{gathered} \text{Volume}=\text{length}\times\text{breadth}\times height \\ \Rightarrow\text{Volume}=(37-2x)\times(37-2x)\times x \end{gathered}[/tex]We now simplify the above as:
[tex]\begin{gathered} \text{Volume}=(37-2x)\times(37-2x)\times x \\ \Rightarrow\text{Volume}=(1369-148x+4x^2)\times x \\ \Rightarrow\text{Volume}=1369x-148x^2+4x^3 \\ \Rightarrow\text{ V(x)}=1369x-148x^2+4x^3 \end{gathered}[/tex]Now that we have obtained the expression for the volume of the box, we now have to find the value of x that maximizes it.
This is done as follows:
Method
- Differentiate the function V(x) with respect to x, and equate to zero as follows:
[tex]\begin{gathered} \Rightarrow V^1\text{(x)}=1369-296x^{}+12x^2 \\ \text{Equating to zero:} \\ 1369-296x^{}+12x^2=0 \\ \text{The roots of the equation are:} \\ \Rightarrow x=6.167\text{ and x = }18.5 \end{gathered}[/tex]Now we have to find the second derivative of V(x) in order to confirm which value of x makes the function V(x) a maximum
Thus:
[tex]\begin{gathered} \Rightarrow V^{11}\text{(x)}=-296^{}+24x^{} \\ \text{when x = 6.167} \\ \Rightarrow V^{11}\text{(6.167)}=-296^{}+24(6.167)=-296+148.008=-148 \\ \text{when x = }18.5 \\ \Rightarrow V^{11}\text{(18.5)}=-296^{}+24(18.5)=-296+444=148 \end{gathered}[/tex]Now since the second derivative is a negative number when x = 6.167, we now know for sure that it is that value of x that maximizes the function V(x), and not x = 18.5.
Thus, we can conclude that the value of x that maximizes the volume of the box is:
x = 6.17 inches (to 2 decimal places)
If we had been asked to find the value of x that minimizes the volume, the answer will have been x = 18.5, because this value of x made the second derivative of V(x) positive.
Now, the maximum volume of the box is obtained by simply substituting the value of x that maximizes the function into the original expression for V(x), as follows:
[tex]\begin{gathered} V(x)=1369x-148x^2+4x^3 \\ \text{when x= 6.167} \\ \Rightarrow\text{ V(6.167)}=1369(6.167)-148(6.167)^2+4(6.167)^3 \\ \Rightarrow\text{ V(6.167)}=8442.623-5628.720+938.171 \\ \Rightarrow\text{ V(6.167)}=3752.074in^3 \\ \Rightarrow\text{ V(6.167)}=3752.07in^3\text{ (to 2 decimal places)} \end{gathered}[/tex]