Expressions and perimeter

Question

The length of the rectangle is 2x + 3 and it’s width is x + 5

Answer 1

the perimeter is 2(L+W)

=2(2x+3 + x+5)

=2(3x+8)

=6x+16

Area

LxW

= (2x+3)(x+5)

=2x^2 + 13x + 15

If you knew the area or perimeter

you could solve for x and for the length & width

If you wanted maximum area for the given perimeter

then the rectangle must be a square with L=W

then 2x+3 = x+5

x=2

then length = 7 = width

perimeter = 4(7) = 28

and area = 7^2 = 49