How can you solve an equation with variables?

Answer 1

That depends a lot on the type of equation. A common method, that works for many of the simpler equations, is to do one or more operations to isolate the variable you want to solve for on the left side. The basic principles are (1) whatever you do on one side of the equation, you have to do on the other side as well; (2) choose your operations so as to get rid of anything that is not the variable. Often this involves using inverse operations. As an example, solve:

2x + 3 = 15

The idea is to isolate the "x" on the left. First, to get rid of the "+3", do the inverse operation - subtract 3 on both sides. The result is:

2x = 12

Next you want to get rid of the "2". Since there is a multiplication, you do the inverse operation - divide by 2. The result is:

x = 6