the length of a rectangle exceeds its breadth by 5m If the breadh were doubled and the length reduced by - Maths - Quadratic Equations

Question

the length of a rectangle exceeds its breadth by 5m If the
breadh were doubled and the length reduced by 9m,the area of
rectangle would have have increased by 140m2 Find its
dimensions

Harsh Kumar · Accepted Answer

breadth=x
length=x+5
area=x*(x+5)=x2 +5x
breadth doubled=2x
length reduced by 9m= x+5-9=x-4
new area=2x*(x-4)=2x2 -8x
therefore
2x2 -8x=x2 +5x+140
x2 -13x-140=0
x2 -20x+7x-140=0
x(x-20)+7(x-20)=0
x=20 or -7
breadth=20
length=25

the length of a rectangle exceeds its breadth by 5m.If the breadh were doubled and the length reduced by 9m,the area of rectangle would have have increased by 140m2 .Find its dimensions.

the length of a rectangle exceeds its breadth by 5m.If the breadh were doubled and the length reduced by 9m,the area of rectangle would have have increased by 140m².Find its dimensions.