How do you solve equations with like terms

You combine them

Step-by-step explanation:

Take for example 3x+6x=90

3x and 6x are like terms, so you add their coefficients and leave x:

(3+6) x=90 - > 9x=90

Next, you divide both sides by 9 to get x by itself:

(9/9) x=90/9 - > x=10