The present dimensions are : length = 12 feet
width = 9 feet
Area = 12* 9 = 108 feet squared
If the dimensions are increased by x feet the dimensions are :
length = 12 + x
width = 9+ x
Area = ( 12+x)( 9+x)
new area = initial area * 2
( 12+ x)( 9+ x) = 2 * 108
12*9 + 12x + 9x + xx = 216
108 + 21 x + x^2 = 216
x^2+ 21x = 216-108
x^2 + 21x = 108
x^2 + 21x -108 = 0
let us plug a= 1 b= 21 c= -108 in quadratic formula
x= [-21 + / - ( 21^2 - 4* 1 * -108 )^(1/2 ]/ 2* 1
x= 4.27
Answer :
Both sides are increased by 4.27 feet .
