Mathematics question

How can you solve an equation with a variable on both sides? complete the explanation. you can solve the equation by using *(blank)* operations to get the variable terms on one side of the equal sign and the constant terms on the *(blank)* side. then *(blank)* both sides by the coefficient of the resulting variable term.

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)