1) 2(3x + 1) - x ≤ 3(x + 4), 2) 7x + 4(x - 2) > 6(1 + 3x),
6х + 2 - х ≤ 3х + 12, 7х + 4х - 8 > 6 + 18x,
5х + 2 ≤ 3х + 12, 11x - 8 > 6 + 18x,
5х - 3х ≤ 12 - 2, 11x - 18x > 6 + 8,
2х ≤ 10, -7x > 14,
х ≤ 5, x < - 2,
х ∈ (-∞; 5]; x ∈ (-∞; -2);
3) 2(x - 1) - 3(x + 2) < 6(1 + x), 4) 7(y + 3) - 2(y + 2) ≥ 2(5y + 1),
2x - 2 - 3x - 6 < 6 + 6x, 7y + 21 - 2y - 4 ≥ 10y + 2,
-x - 8 < 6 + 6x, 5y + 17 ≥ 10y + 2,
-x - 6x < 6 + 8, 5y - 10y ≥ 2 - 17,
-7x < 14, -5y ≥ -15,
x > -2, y ≤ 3,
x ∈ (-2; +∞); y ∈ (-∞; 3].
1) 6 1/4* 2/25 = 25/4 * 2/25 = 1/2
2)5/13* 9 1/10 = 5/13 * 91/10 = 7/2 = 3 1/2
3)5 1/5 *25/38 = 26/5 * 25/38 = 65/19 = 3 8/19
4) 7/9 * 1 4/5 = 7/9 * 9/4 = 7/4 = 1 3/4
5) 12 3/5 * 5 = 63/5 * 5/1 = 63 6) 13 * 2 1/26 = 13/1 * 53/26 = 53/2 = 26 1/27) 1 1/15 * 3 8) 2 * 8 3/4