How to do elimination in algebra? ?

Elimination is another word for canceling out, this usually occurs in equations. This also occurs when you are trying to figure out the points of a graph

Take a look of this picture of an equation that deals with elimination:

2x+3y=20

-2x+y=4

0+4y=20
     4y=24

y=6.

Cancel the numbers out to get the variable by itself, in order to get the variable by itself you need to divide. 

Hope this helped :)
Have a great day