4x2 - 12x = 7
4x2 - 12x - 7 = 0
4x2 + 2x - 14x - 7 = 0
Take 2x common from first 2 terms and -7 from last 2 terms
2x(2x + 1) - 7(2x + 1) = 0
Now take 2x+1 whole common from full equation
(2x + 1)(2x - 7) = 0
Now put both equal to 0 separately
2x + 1 = 0
2x = -1
x = -1/2
And
2x - 7 = 0
2x = 7
x = 7/2
So (-1/2 , 7/2) will be the answer .
