SOLUTION: the length of a rectangle is 10 m and its breadth is 5m. if the length and the breadth is each increased by the same amount, the area of the rectangle is doubled. find the length o

Algebra ->  Rectangles -> SOLUTION: the length of a rectangle is 10 m and its breadth is 5m. if the length and the breadth is each increased by the same amount, the area of the rectangle is doubled. find the length o      Log On


   

Question 1055916: the length of a rectangle is 10 m and its breadth is 5m. if the length and the breadth is each increased by the same amount, the area of the rectangle is doubled. find the length of the bigger rectangle, correct to one decimal place
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
the bigger rectangle:
Lw = A
(10+x)(5+x) = 100m^2 area of the rectangle is doubled
50 + 15x + x^2 = 100
x^2 + 15x - 50 = 0
x = %28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x = (-15 + 5√17 )/2
Solve for x ( correct to one decimal place)
L = x%2B10