Question

Answer 1

\(h,4x^2-4x-3x^2+15-x^2=x-3-x-4\\ =-4x+15=-7\\ -4x=-7-15\\ -4x=-22\\ x=\dfrac{11}{2}\)

Answer 2

\(\Leftrightarrow4x^2-4x-3x^2+15-x^2=-7\Leftrightarrow-4x=-22\Leftrightarrow x=\dfrac{11}{2}\)

Answer 3

=> 4x^2 - 4x - 3x^2 + 15 - x^2 = x - 3 - x -4

=> -4x + 15 = -7

=> -4x = -22

=> x = 5,5