Question

3×(2+x)-15=31

Answer 1

3×(2+x)-15=31 <=> 6+3x-15=31<=> 3x=40 <=> x=\(\dfrac{40}{3}\)

Answer 2

\(3\times\left(2+x\right)-15=31\)

\(3\times\left(2+x\right)=31+15\)

\(3\times\left(2+x\right)=46\)

\(2+x=46:3\)

\(2+x=15,3\)

\(x=15,3-2\)

\(x=13,3\)