195. Найдите значение выражения: 1) 0,6(4y – 18) – 0,4(5 – 7у) при y = 2 4/13; 2) 5 1/4 (12-c) + 3 1/4 (-c – 8) при c = -0,4.

1) $$2.4y - 10.8 - 2 + 2.8y = 5.2y - 12.8$$. $$y = 30/13$$. $$5.2 * (30/13) - 12.8 = (52/10) * (30/13) - 12.8 = (4 * 30)/10 - 12.8 = 12 - 12.8 = -0.8$$
2) $$21/4 (12 - c) + 13/4 (-c - 8) = 21/4 * 12 - 21/4 c - 13/4 c - 13/4 * 8 = 63 - 34/4 c - 26 = 37 - 17/2 c$$. $$c = -0.4$$. $$37 - 17/2 * (-0.4) = 37 + 17/2 * 0.4 = 37 + 17 * 0.2 = 37 + 3.4 = 40.4$$