{ ( 4 . x + 28 ) . 3 + 55 } = 35 . 5
{ ( 4 . x + 28 ) . 3 + 55 } = 175
{ ( 4 . x + 28 ) . 3 } = 175 - 55
{ ( 4 . x + 28 ) . 3 } = 120
{ ( 4 . x + 28 ) } = 120 : 3
4 . x + 28 = 40
4 . x = 40 - 28
4 . x = 12
x = 12 : 4
x = 3
dương bạn lớp mấy ở đâu học trường nào
\(\left[\left(4x+28\right)\cdot3+55\right]:5=35\)
\(\Leftrightarrow\left(4x+28\right)\cdot3+55=35\cdot5\)
\(\Leftrightarrow\left(4x+28\right)\cdot3+55=175\)
\(\Leftrightarrow\left(4x+28\right)\cdot3=175-55\)
\(\Leftrightarrow\left(4x+28\right)\cdot3=120\)
\(\Leftrightarrow4x+28=120:3\)
\(\Leftrightarrow4x+28=40\)
\(\Leftrightarrow4x=40-28\)
\(\Leftrightarrow4x=12\)
\(\Leftrightarrow x=12:4\)
\(\Leftrightarrow x=3\)
(4xx+28x3+55=35x5
4xx+28x3 =175-55
4xx+28. =125:3
4xx. =44+28
X. =44:4=11
\(\left[\left(4x+28\right).3+55\right]\div5=35\)
\(\left[\left(4x+28\right).3+55\right]=175\)
\(\left(4x+28\right).3=120\)
\(4x+28=40\)
\(4x=12\)
\(x=3\)
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