Question

Докажите тождество (x-12)(x-3)-(x-1)(x-6)=6​

Answer 1

$(x-12)(x-3)-(x-1)(x-6)=6\\x^2-3x-12x+36-x^2+6x+x-6=6\\x^2-3x-12x-x^2+6x+x=6-36+6\\-8x=-24\ /:(-8)\\x=3$