Question

the width of a rectangle is 9 inches less than its length and the area is 36 square inches. what are the length and width of the rectangle

Answer 1

12 and 3

Explanation:

Let x= length

If you draw a rectangle. two sides would be the length x. The other two sides would be (x-9).

(length)(width) = Area

(x)(x-9) = 36

x^2 - 9x = 36 Substitute in x and x-9 for the length and width

x^2 - 9x - 36 =0 Subtract 36 from both sides

(x-12)(x+3) = 0 We are looking for 2 number that add to -9 and mult. to -36

x-12=0 and x+3=0 Set both factors to 0 and solve

x = 12 and x =-3. It does not make sense that a length could be -3 so we reject that answer. If the length is 12, then the width is 3