Question

the length of a rectangle is 3 cm more than its width and its area is 40cm sq.find dimensions of rectangle

Answer 1

Let width of rectangle be x
Then it's length will be (x+3)
We know that,
Area=Length *Breadth
40=(x+3)x
0=$x^{2}$+3x-40
0=$x^{2}$+8x-5x-40
0=x(x+8)-5(x+8)
0=(x+8)(x-5)
Case 1:
x+8=0
x=-8(it will be rejected as dimensions cannot be negative)
Case 2:
x-5=0
x=5
Therefore,
width=x=5cm
length=x+3=8cm

Answer 2

hey friend,

let the width be x cm , length be x+3 cm

Area=length * breadth
40=x(x+3)
x^2 +3x=40
x^2+3x-40=0
x^2+8x-5x-40=0
x(x + 8)-5(x+8)=0
(x+8) (x-5)=0
x+8=0 or x-5=0
x =-8 or x=5

As length cannot be negative, x = 5

Width=5cm

Length=8cm

#hope it helps.....