Question

Question One

Farmer Jones has 140 feet of fencing to construct a rectangular corral.

If x represents the width of the corral, which function can be used to express the area A of the

corral as a function of x?

A

A(x) = 70.0

B

A(z) = 2(70 - 2)

C

A(x) = a(140 – 2)

D

A(z) = x(140 – 22)

Answer 1

`A(x)=x(70-x)`

Explanation:

Let

x ----> the width of the rectangular corral

y ----> the length of the rectangular corral

we know that

The perimeter of the rectangular corral is equal to

`P=2(x+y)`

`P=140\ ft`

so

`140=2(x+y)`

simplify

`70=(x+y)`

`y=70-x` ----> equation A

Remember that

The area of a rectangle is equal to

`A=xy` ----> equation B

substitute equation A in equation B

`A=x(70-x)`

Convert to function notation

`A(x)=x(70-x)`