Question

x(2-x)+(x-4)(x+4)=0

Answer 1

\(x\left(2-x\right)+\left(x-4\right)\left(x+4\right)=0\)

\(\Leftrightarrow2x-x^2+x^2-16=0\)

\(\Leftrightarrow2x=16\)

\(\Leftrightarrow x=8\)

Vậy: \(S=\left\{8\right\}\)

Answer 2

x ( 2 - x ) + ( x² - 16 )  = 0

-x² + 2x + x² - 16 = 0

2x - 16 = 0

=> 2 ( x - 8 ) = 0

=> x - 8 = 0

x = 8

Vậy x = 8