a) \(132,5-2x=29,9\)
<=>\(2x=132,5-29,9\)
<=>\(2x=102,6\)
<=>\(x=102,6:2\)
<=>\(x=51,3\)
b) \(18-5x=8\)
<=>\(5x=18-8\)
<=>\(5x=10\)
<=>\(x=10:5\)
<=>\(x=2\)
c) \(2x+14=26\)
<=>\(2x=26-14\)
<=>\(2x=12\)
<=>\(x=12:2\)
<=>\(x=6\)
d) \(x-105:21=15\)
<=>\(x-5=15\)
<=>\(x=15+5\)
<=>\(x=20\)
e) \(315+\left(125-x\right)=81\)
<=>\(125-x=81-315\)
<=>\(125-x=-234\)
<=>\(x=125--234\)
<=>\(x=125+234\)
<=>\(x=359\)
K CHO MINK NHA