The length of a rectangle is 11 less than 9 times the width. The perimeter of the rectangle is 18 inches

Length = 7   Width = 2

Step-by-step explanation:

L = Length

W = Width

L=9w-11

2L+2W=18

2(9W-11) + 2W = 18

18W - 22 +2W = 18

20W -22 = 18

20W = 40

W = 2

L = 9(2)-11

L=18-11

L=7

i need a picture

step-by-step explanation:

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240