Question

25-12x+(x-5)(x+5)-(5-x)

Answer 1

$25-12x+(x-5)(x+5)-(5-x)$

$25-12x+x^2+5x-5x-25-5+x$

$x^2-5-11$

$x^2=-11-5$

$x^2=-6$

$x=-6:2$

x$x=-3$

 

Answer 2

25-12x+x+x^2-5^2-5+x=20-11x+x-5^2=-5-10x