A rectangle is 14 cm long and 10 cm wide . If the length is reduced by x cms and its width is increased also by x cms so as to make it a square, then its area changes by :
- 4
- 144
- 12
- 2
Answer: 4
Explanation: Area = 14 × 10 = 140 sq.cm
New length = ( 14 – x)
New width = ( 10 + x)
14 – x = 10 + x
2x = 4
x = 2
New Area = ( 14 – 2) × ( 10 + 2) = 144
change is area = ( 144 – 140) sq.cm = 4 sq.cm