Question

the length of a rectangle is 3 times its width. if the width is increased by 2cm and the length is increased by 4cm, its area is doubled. find the original dimensions of the rectangle.

Answer 1

let the width be X and length be 3x
now,X+2=width and 3x+4=length
(X+2)(3x+4)= 3x2+ 10x +8=6x2

X=4 and length = 12

Answer 2

Answer:

Step-by-step explanation:

Let L & B be the Length &width of rectangle.

L= 3 times of width ie 3B

Area of rectangle = LxB = 3B x B

If Length of rectangle increased by 4cm .ie 3B+4

Width increased by 2cm ie B+2

Area will be doubled ie (3B+4)(B+2)=2× 3BxB

3B(B-4)+2(B-4)=0

(B-4)(3B+2)=0

B= 4 or -2/3

Since size will not be in negative side.so

Width of Rectangle = 4 cm

Length of Rectangle = 3B =3×4= 12 cm.