270+6[x-15]=450
6[x-15]=450-270
6[x-15]=180
x-15=180:6
x-15=30
x=30+15
x=45
\(270+6.\left(x-15\right)=450\)
\(\Leftrightarrow6.\left(x-15\right)=180\)
\(\Leftrightarrow x-15=30\)
\(\Leftrightarrow x=45\)
Vậy \(x=45\)
270 + 6 [ x - 15 ] = 450
6 [ x - 15 ] = 450 - 270
6 [ x - 15 ] = 180
x - 15 = 180 : 6
x - 15 = 30
x = 30 + 15
x = 45
Vậy , x = 45
tìm x biết 120 [ 124 - 4x ] - 10 = 5
Bài làm :
\(270+6.\left(x-15\right)=450\)
\(\Leftrightarrow6.\left(x-15\right)=450-270\)
\(\Leftrightarrow6.\left(x-15\right)=180\)
\(\Leftrightarrow x-15=180\div6\)
\(\Leftrightarrow x-15=30\)
\(\Leftrightarrow x=45\)
Vậy x=45