Question 415129

let number is x, then square of it = x^2


x^2 = x+12 

=> x^2 -x -12 =0

=> x^2 -4x+ 3x -12 =0

=> x(x-4) +3(X -4) = 0

=>(X-4)(x+3 ) = 0


so, x = 4  , x= -3 

if number is positive then only x=4,

otherwise x= -3 and 4 also because -3 is also a number and difference of -3 and 

its square i.e 9 is 12.