помагите..) x^2-20x=-5x-13-x^2

Question

помагите..)

x^2-20x=-5x-13-x^2

Answer 1

x^2 -20x +5x +13 +X^2 =0

2x^2 -15x +13 =0

D = 225 -4*2*13= 225-104=121

x = 1    x  = 6.5