Question

4 + x ( x - 4 ) = x
como resolver esta equação?

Answer 1

4 + x - 4x= x
x - 4x - x = 4
-4x = 4
x= 4/-4
x=-1

Answer 2

$4+x^2-4x=x \\ x^2-4x-x+4=0 \\ x^2-5x+4=0$

Δ=9

$\frac{-5- \sqrt{9} }{2*1} = \frac{-5-3}{2} = \frac{-8}{2} = -4$$\frac{-5+3}{2} \frac{-2}{2} = -1$