265,024 views
31 votes
31 votes
I need help with this please check work after i cant get any wrong

I need help with this please check work after i cant get any wrong-example-1
User Michael Burger
by
2.4k points

1 Answer

20 votes
20 votes

SOLUTION:

Case: Area of triangle (maximum value) application

Given: expressions for the base and height of the triangle

length of base = x

height = 2 (24-2x)

Required: Equate Area, A(x) = (1/2) bh. Find the maximum area

Method:

The Area, A(x) is given as:


\begin{gathered} A(x)=\text{ }(bh)/(2) \\ A(x)=\text{ }(x*2(24-2x))/(2) \\ A(x)=\text{ }x(24-2x) \\ A(x)=\text{ }24x-2x^2 \\ \text{Differentiating;} \\ A^(\prime)(x)=\text{ }24-4x^{} \\ \text{The maximum area is obtained where A'(x)=0} \\ 0=\text{ }24-4x^{} \\ 4x=24 \\ \text{Divide both sides by 4} \\ x=\text{ 6} \end{gathered}

The maximum area therefore is A(x)=


\begin{gathered} A(x)=\text{ }24x-2x^2 \\ \text{Where x=6} \\ A(6)=\text{ }24(6)-2(6)^2 \\ A(6)\text{ = 144 -2(36)} \\ =\text{ 14}4-72^{} \\ A=\text{ 72} \end{gathered}

Final answer:

The maximum potential area is 72 square inches.Option (D)

User Jack Freeman
by
2.6k points