a) y+2,3=15,724
=>y =15,724 - 2,3
=>y = 13,424
b) 127-(y-15)=86
=> y-15 = 127-86
=> y-15 = 41
=> y = 41+15
=> y = 56
c) 2 x (y-12)+18 = 164
=> 2 x (y-12) = 146
=> y-12 = 73
=> y = 73 + 12
=> y = 85
a) \(y+2,3=15,724\)
\(y=15,724-2,3\)
\(y=13,424\)
b) \(127-\left(y-15\right)=86\)
\(y-15=127-86\)
\(y-15=41\)
\(y=41+15\)
\(y=56\)
c) \(2\cdot\left(x-12\right)+18=164\)
\(2\cdot\left(x-12\right)=164-18\)
\(2\cdot\left(x-12\right)=146\)
\(x-12=146:2\)
\(x-12=73\)
\(x=73+12\)
\(x=85\)
Câu a) y+2,3=15,724
y=15,724-2,3
y=13,424
Vậy y= 13,424
Câu b) 127-(y-15) = 86
( y-15) = 127-86
y-15= 41
y=41+15
y=56
Vậy y =56
Câu c) \(2\times\left(y-12\right)+18=164\)
\(2\times\left(y-12\right)=164-18\)
\(2\times\left(y-12\right)=146\)
\(y-12=146:2\)
\(y-12=73\)
\(y=73+12\)
\(y=85\)
Vậy