hezkid
contestada

The length of a rectangle is three times its breadth if the breadth is decreased by 2 m and breadth increased by 4 m the area of the rectangle is decreased by 1/3
a) form a quadratic equation ​

Respuesta :

mhanifa

Answer:

Let the breadth is x, then the length is 3x.

The area is:

  • A = lw = 3x*x = 3x²

The breadth is decreased by 2 m:

  • w = x - 2

The length is increased by 4m:

  • l = 3x + 4

The area is now:

  • (x - 2)(3x + 4) = 3x² - 1/3(3x²)
  • 3x² +  4x - 6x - 8 = 2x²
  • x² - 2x - 8 = 0
  • x² - 2x + 1 = 9
  • (x - 1)² = 3²
  • x - 1 = 3
  • x = 4

The breadth was 4 m and the length  12 m