Question

Find the length and width of a rectangle that has the given perimeter and a maximum area. Perimeter: 392 meters

Answer 1

Answer:

the length is 98 meters and the width 98 meterss

Step-by-step explanation:

We have that the length is l and the width is w, we know that:

P = 2 * w + 2 * l

if we solve for it, we have:

l = P / 2 - w

Now, we know that the area is:

A = l * w

if we replace l, we are left with:

A = (P / 2 - w) * w

A = P * w / 2 - w ^ 2

we derive to know the maximum area and we equal 0 and we have:

A '= P / 2 - 2 * w

0 = P / 2 - 2 * w

w = P / 4

now for him:

l = P / 2 - P / 4

l = P / 4

Therefore, if we replace:

l = 392/4 = 98

w = 392/4 = 98

For the maximum area the length is 98 meters and the width 98 meterss