Question

Найдите корни уравнения
1) (x + 1)(2x - 3)=7
2)x(3x - 2) = (5x + 2 )( x-1)
3) ( x - 8 )(x - 9) + 52 = 0
4) x( x+7 )=( 2-x )( x+2)

Answer 1

1) 2x^2-3x+2x-3=7; 2x^2-x-10=0; D=1+4×2×10=81; x1=(1+9)/4=10/4; x2=(1-9)/4=-2;
2)