Question

tìm x

a) 56 - ( x+31) = 12

b) ( 2x +5 ) . 4=6²

tính

360-

Answer 1

a) \(56-\left(x+31\right)=12\)

\(\Rightarrow x+31=44\)

\(\Rightarrow x=13\)

b) \(\left(2x+5\right)\cdot4=6^2\)

\(\Rightarrow2x+5=9\)

\(\Rightarrow2x=4\)

\(\Rightarrow x=2\)

Answer 2

a) 56 - ( x+31) = 12

\(\Rightarrow\) -x + 25 = 12

\(\Rightarrow\) -x = -13

\(\Rightarrow\) x = 13

b) ( 2x +5 ) . 4=6²

\(\Leftrightarrow\) (2x + 5) . 4 = 36

\(\Rightarrow\) 2x + 5 = 9

\(\Rightarrow\) 2x = 4

\(\Rightarrow\) x = 2