How to solve equation with one variable

Hope this RANDOM example helps u understand the concept better

An equation has an equal sign. This makes it possible to find the one value the variable can be to "balance" the equation. 

To solve an equation, we isolate the variable (get the variable by itself on one side of the equation). This is done by "undoing" the operation on the variable. 

Example -  

 

Iknow one of the answers is a and maybe b but not 100% sure about b