Question

2 questions

when can you combine like terms?
when can you NOT combine like terms?

( do not put the definiton of like terms i only need these questions answered)

Answer 1

You can combine like terms when they have the same variable, same category, or same coefficient. You CANNOT combine like terms when they have none of the attributes listed above. For example, you can combine 7x and 20x, just like you can combine 3 and 4, but you can't combine 3x & 5(x^2), or 9x and 73.