Question

Найдите корни уравнения x^2-7x=8.

Answer 1

x^2-7x=8
x^2-7x-8=0
D=(-7)^2-4*1*(-8)=49+32=81
x1=7-9/2=-1
x2=7+9/2=8

Answer 2

x^2 - 7x -8=0
D= 49+32=81=9^2
x1=(7+9)/2=8
x2=(7-9)/2=-1