BÀI 1:
a, 15.(-37)+450 = -555 + 450 = -105
b, (-1/7+2/5) + (-6/7) = 9/35 + (-6/7) = -3/5
c, 146/13 - (18/7 + 68/13)
=146/13 - 710/91 = 291/91
BÀI 2:
a, 2.x+35=15
2.x = 15 - 35 = -20
x = -20÷2 = -10
b, x - 17/5 = 6/5
x = 17/5 + 6/5 = 23/5
c,║3x - 1/2║ = 3/4
=> 3x - 1/2 = 3/4 hoặc 3x - 1/2 = -3/4
3x = 3/4 + 1/2 = 5/4 3x = -3/4 + 1/2 = -1/4
x = 5/4 ÷ 3 = 5/12 x = -1/4 ÷ 3 = -1/12