Вправи: 1228

1228. Спростіть вираз:

1) –7(а – 2b + 2) – 2(5а – 5) = –7a + 14b – 14 – 10a + 10 = 14b – 17a – 4;

2) a(3x – 2y + 5) – 2a(–2x – y) = 3ax – 2ay + 5a + 4ax + 2ay = 7ax + 5a;

3) 213a – 116a – 59a = 226a – 116a – 59a = 76a – 59a = 2118a – 1018a = 1118a;

4) –214x + 1,6x – 58x = –2,25x + 1,6x – 0,625x = –1,275x;

5) –(334b – 29) + 4(118b – 16) = –154b + 29 + 4 • 98b – 4 • 16 = –154b + 29 + 92b – 23 = –154b + 29 + 184b – 69 = 34b – 49;

6) 2 • (138x – 34y) – (312x – 2y) = 2 • 118x – 2 • 34y – 72x + 2y = 114x – 32y – 72x + 2y = 114x – 32y – 144x + 42y = –34x + 12y.