315 + (146 - x) = 472
146 - x = 472 - 315
146 - x = 157
x = 146 - 157
x = -11
5x - 8 = 612
5x = 612 + 8
5x = 620
x = 620 : 5
x = 124
132 : x = 23 - 12
132 : x = 11
x = 132 : 11
x = 12
* \(315+\left(146-x\right)=472\)
\(-x=472-315-146\)
\(-x=11\Rightarrow x=-11\)
* \(5x-8=612\)
\(5x=612+8\)
\(5x=620\)
\(x=620:5=124\)
* \(132:x=23-12\)
\(132:x=11\)
\(x=132:11=12\)
(Nhớ k cho mình với nhá!)
a) 315+(146-x)=472
146-x=472-315
146-x=157
x=146-157
x=-11
Vậy x=-11
b)5x-8=612
5x=612+8
5x=620
x=620:5
x=124
Vây x=124
c)132:x=23-12
132:x=11
x=132:11
x=12
Vậy=12