40 PTS ! The length of the rectangle is 2 ft more than its width. The area of the rectangle is 80 square feet. Find the width of the rectangle.

Respuesta :

Answer:

The length of a rectangle is 2 feet more than it's width. How do you find the dimensions of the rectangle if its area is 63 square feet?

Step-by-step explanation:

x(x+2) = 63

x^2 + 2x = 63

x^2 + 2x - 63 = 0

Quadratic formula with numbers plugged in: (-2 +or- sqrt(4 - 4* 1 * -63))/2 becomes

-2 +or- sqrt(256)/2 so (-2 +or- 16)/2 therefore -18/2 or 14/2. Discard negative result.

x = 7. 63/7=9. Sides are 7ft and 9ft.

Answer:

  • 8 ft

Step-by-step explanation:

Given

  • The length l = w + 2
  • The area  lw = 80

Substitute l and solve the following for w:

  • w(w + 2) = 80
  • w² + 2w = 81
  • w² + 2w + 1 = 81
  • (w + 1)² = 9²
  • w + 1 = 9
  • w = 8

The width is 8 ft