How do you do this problem ?

anonymous

Write the perimeter of the rectangle as a simplified polynomial. Then factor this polynomial completely.

7x + 90

x2 + 12x

(x + 10)(x + 9)

2(x + 10)(x + 9)

2(x + 12)(x + 7)

(2x + 10)(x + 9)

pi-r-squared

Hi,

Combining x² + 12 x and 7x + 90 gives an area of:

x² + 12 x and 7x + 90 = x² + 12 x + 7x + 90 = x² + 19x + 90

Since area = length x width, then x² + 19x + 90 = (x + 10)(x+ 9)

Since perimeter = 2(length)(width), then

perimeter = 2(x + 10)(x+ 9)

That is answer b. I hope that helps!! :-)

harry-m

perimeter=2( x2 + 12x + 7x + 90)

=2(x2 + 19x + 90)

=2(x + 10)(x + 9)