The LCD is x ( x - 4)
So we have
(x - 3 ) x + 4x (x - 4) 3x (x - 4)
______ ________ = ________
x(x - 4) x(x - 4) x(x - 4)
Since all the denominators are the same, we can forget them and work with the numerators
(x - 3)x + 4x(x - 4) = 3x (x - 4)
x^2 - 3x + 4x^2 - 16x = 3x^2 - 12x simplify
5x^2 - 19x = 3x^2 - 12x rearrange as
2x^2 - 7x = 0
x( 2x - 7) = 0 set both factors to 0 and solve for x
x = 0 2x - 7 = 0
2x = 7
x = 7/2
x = 0 cannot be a solution because it makes an original denominator = 0
So....x = 7/2 is the only solution
I'll leave the checking for you, GameMaster....