bài 1:
a, 3 x (y - 1)= 2013 b, 2015 - 2 ( y - 5 ) = 5
y - 1 = 2013 : 3 2 ( y - 5 ) = 2015 - 5
y - 1 = 671 2 ( y - 5) = 2010
y = 671 + 1 y - 5 = 2010 : 2
=> y = 672 y - 5 = 1005
y = 1005 + 5
=> y = 1010
c, 2 x ( y + 3 ) - 12 = 2010 d, 2014 - 3 x ( y +5) = 4
2 x ( y + 3 ) = 2010 + 12 3 x ( y + 5 ) = 2014 - 4
2 x ( y + 3 ) = 2022 3 x ( y + 5 ) = 2010
y + 3 = 2022 : 2 y + 5 = 2010 : 3
y + 3 = 1011 y + 5 = 670
y = 1011 - 3 y = 670 - 5
=> y = 1008 => y = 665
a, \(3\left(y-1\right)=2013\)
\(\Rightarrow y-1=2013:3\)
\(\Rightarrow y-1=671\)
\(\Rightarrow y=672\)
b, \(2015-2\left(y-5\right)=5\)
\(\Rightarrow2015-2y-10=5\)
\(\Rightarrow2015-2y=15\)
\(\Rightarrow2y=2015-15\)
\(\Rightarrow2y=2000\)
\(\Rightarrow y=1000\)
c, \(2\left(y+3\right)-12=2010\)
\(\Rightarrow2y+6=2022\)
\(\Rightarrow2y=2016\)
\(\Rightarrow y=1008\)
d, \(2014-3\left(y+5\right)=4\)
\(\Rightarrow3y+15=2010\)
\(\Rightarrow3y=1995\)
\(\Rightarrow y=665\)
