Question 835810
There are no formulas, use the rules of arithmetic.
I'll do one and you do the same.
Move the knowns to one side, unknowns to the other.
Use additive and multiplicative inverses, distributive and commutative properties
Add {{{8}}} to both sides (additive inverse).
{{{x/2-8=7}}}
{{{x/2-8+8=7+8}}}
{{{x/2+0=15}}}
{{{x/2=15}}}
Multiply both sides by {{{2}}}(multiplicative inverse)
{{{2(x/2)=2*15}}}
{{{(2/2)x=30}}}
{{{(1)x=30}}}
{{{highlight_green(x=30)}}}
Then check your answer in the original equation.
{{{x/2-8=7}}}
{{{30/2-8=7}}
{{{15-8=7}}}
{{{7=7}}}
True, right answer.