Answer:
Step-by-step explanation:
Let length = x and width =y
Area of rectangle = 20 square inches
x*y = 20
xy = 20 -------------(I)
Perimeter = 18 cm
2*length + 2*width = 18
2x + 2y = 18
Divide the entire equation by 2
x + y = 9
x = 9 -y -----------------(II)
Substitute x = 9 - y in equation (I)
(9 - y)*y = 20
9y - y² = 20
0 = 20 +y² - 9y
y² - 9y + 20 = 0
y² - 4y - 5y + 20 = 0
y(y - 4) - 5(y - 4) = 0
(y -4)(y -5) = 0
y - 4 = 0 ; y- 5 = 0
y = 4 ; y = 5
Length = 4 cm and width = 5 cm
