Вправи: 809

809. Розв’яжіть рівняння:

1) (x – 2)(x + 3) = –6;x2 + 3x – 2x – 6 + 6 = 0;x2 + x = 0;x(x + 1) = 0;x1 = 0 або x + 1 = 0; x2 = –1;	2) 13x(x + 9) = 18x(x – 16); |x248x(x + 9) = 3x(x – 16);8x2 + 72x = 3x2 – 48x;8x2 + 72x – Зх2 + 48x = 0;5х2 + 120x = 0;5x(x + 24) = 0;5x = 0 або x + 24 = 0;x1 = 0; x2 = –24;
3) (Зх – 1)2 = (x – 3)2;9x2 – 6x + 1 = x2 – 6x + 9;9x2 – 6x + 1 – x2 + 6x – 9 = 0;8x2 = 8;x2 = 1;x1 = 1; x2 = –1 ;

4) (2x + 1)(3x – 1) = x(x – 2) + 3(x – 13);

6х² – 2x + 3x – 1 = x² – 2x + 3x – 1;

6х² – x² = 0;

5х² = 0;

x² = 0;

x = 0.