Вправи: 726

726. Зведіть рівняння до вигляду ах² + bх + с = 0.

1) (x + 1)(x – 2) = 4;

x² – 2x + x – 2 – 4 = 0;

x² – x – 6 = 0.

2) 8х = (x – 4)(x + 4);

8х = x² – 16;

x² – 8х – 16 = 0;

3) (x + 2)² – 13 = з(х – 1);

x² + 4x + 4 – 13 = 3х – 3;

x² + 4x – 9 – 3х + 3 = 0;

x² + x – 6 = 0.

4) 4x² – 5 = 2x(1 + 3х);

4x² – 5 = 2x + 6x²;

4x² – 5 – 2x – 6x² = 0;

–2x² – 2x – 5 = 0 | • (–1);

2x² + 2x + 5 = 0.

5) (x + 3)² – 6 = 8 + 10x;

x² + 6x + 9 – 6 – 8 – 10x = 0;

x² – 4x – 5 = 0.

6) 4(x + 8) = (x – 4)(x + 2);

4x + 32 = x² + 2x – 4x – 8;

4x + 32 – x² – 2x + 4x + 8 = 0;

–x² + 6x + 40 = 0 | • (–1);

x² – 6x – 40 = 0.