Question

2) (x + 8) (5x - 6) - 20 = 5x2;​

Answer 1

$\displaystyle (x + 8) (5x - 6) - 20 = 5x^2\\5x^2-6x+40x-48-20=5x^2\\5x^2-5x^2+40x-6x=48+20\\34x=68\\x=2\\Otvet: \quad 2.$