3x + 4x + 8x - 2( 32 + 8 ) = 30
15x - 2.40 = 30
15x - 80 = 30
15x = 30 + 80
15x = 110
x = 110 : 15
x = 22/3
3x+4x+8x - 2.(32+8) = 30
( 3 + 4 + 8 )x - 2.40 = 30
15x - 80= 30
15x = 30 + 80 = 110
x = 110 : 15 = \(\frac{22}{3}\)
\(3x+4x+8x-2\cdot\left(32+8\right)=30\)
\(\left(3+4+8\right)x-2\cdot40=30\)
\(15x-80=30\)
\(15x=30+80\)
\(15x=110\)
\(x=110:15\)
\(x=\frac{22}{3}\)
Vậy \(x=\frac{22}{3}\)