Explanation: When using the method of elimination, the goal is to eliminate a variable by either adding or subtracting the 2 equations. For this question, you can choose either to eliminate X or Y. I’ll eliminate X as an example:
In order to eliminate a variable, the same variable in both equations must have the same coefficient.
(1) 3x+y=7 (2) 2x+5y=22
Multiply (1) by 2:
(3) 6x+2y=14
Multiply (2) by 3:
(4) 6x+15y=66
Now that X in both equations has the same coefficient of 6, you can subtract the two equations to officially eliminate the variable and solve for Y:
Subtract (4) from (3):
-13y=-52 y=4
Now that you have the value of Y, substitute that into either one of the equations to get X. I’ll use the first equation as an example:
