Answer:
[tex]x=3\\y=6[/tex]
Step-by-step explanation:
[tex]x=y-3\\2x+y=12[/tex]
We have already defined that x = y - 3, replace x for this value.
[tex]2x+y=12\\2(y-3)+y=12[/tex]
Distribute 2.
[tex]2y-6+y=12[/tex]
Add 6.
[tex]2y+y=12+6[/tex]
Combine like terms;
[tex]3y=18[/tex]
Divide by 3.
[tex]y=\frac{18}{3}\\ y=6[/tex]
After having found a variable value, in this case y, replace it in the other equation; x = y - 3, to find x.
[tex]x=y-3\\x=6-3\\x=3[/tex]
