**№1**
12 + (-20) - (-11) + 18 - (-6) - 10 = (12 + 18) + (-20 - 10) + 11 + 6 = 30 - 30 + 17 = 17
**№2**
0,5×(1.6x - 6,4y) - 2,4×(1,5x + y) = 0,8x-3,2y - 3,6x - 2,4y = 4,4x - 5,6y
x=3; y=-4,5
4,4×3 - 5,6×(-4,5) = 13,2 + 25,2 = 38,4
**№3**
3+5/12 - (-(1+1/3)) + (-3/8) = 41/12 + 4/3 - 3/8 = 81/24 + 32/24 - 9/24 = 122/24 = 5+1/12
**№4** у фото, так легше.
**№1**
12 + (-20) - (-11) + 18 - (-6) - 10 = (12 + 18) + (-20 - 10) + 11 + 6 = 30 - 30 + 17 = 17
**№2**
0,5×(1.6x - 6,4y) - 2,4×(1,5x + y) = 0,8x-3,2y - 3,6x - 2,4y = 4,4x - 5,6y
x=3; y=-4,5
4,4×3 - 5,6×(-4,5) = 13,2 + 25,2 = 38,4
**№3**
3+5/12 - (-(1+1/3)) + (-3/8) = 41/12 + 4/3 - 3/8 = 81/24 + 32/24 - 9/24 = 122/24 = 5+1/12
**№4** у фото, так легше.