The length of one side of a rectangle is x + 4. The area of the rectangle is x^2 = 16x + 48. Find an expression in x for the length of the other side.

Answer 1

divide x+4 into x^2 - 16x -48

x^2 -16x = 48

x^2 -16x + 64 = 48 + 64 = 112

(x-8)^2 = 112

x-8 = sqr112 = 4sqr7 = about 10.6

x = 8 + 10.6 = 18.6

x+4 = 22.6

21

area = x^2 = 18.6^2 = 346

346/22.6 = about 15.3 for the other side of the rectangle

16x + 48 = 16(x+3)

divide by x+4

16(x+3)/(x+4) = 16(21.6)/22.6) = about 15.3