Розділ 1. ЦІЛІ ВИРАЗИ » 368

Розв’яжи рівняння. a) (x – 2)(x + 5) = x2 + 2; x2 + 5x – 2x – 10 = x2 + 2; 3x = 10 + 2; 3x = 12|: 3; x = 4. б) (x – 6)(x – 2) – x(x + 2) = 2; x2 – 2x – 6x + 12 – x2 – 2x = 2; –10x = –12 + 2; –10x = x10|: (–10); x = 1. в) (x – 1)(x + 5) = (x + 2)(x + 3); x2 + 5x – x – 5 = x2 + 3x + 2x + b; 4x – 5x = 5 + 6; –x = 11; x = –11. г) (2x + 3)(x – 7) + 6 = (x + 3)(2x + 1); 2x2 – 14x + 3x – 21 + 6 = 2x2 + x + 6x + 3; –11x – 7x = 21x – 6 + 3; –18x = 18|: (–18); x = –1.