Answer:
x=3,y=6
Explanation:
4x-y =6
3x+2y = 21
To use elimination we will multiply the first equation by 2
2(4x-y) =6*2
8x -2y =12
We will add this equation to the second equation to eliminate y
8x -2y =12
3x+2y = 21
-----------------
11x = 33
Divide each side by 11
11x/11 = 33/11
x =3
We still need to solve for y
3x+2y = 21
Substituting x=3
3*3+2y = 21
9+2y =21
Subtract 9 from each side
9-9+2y = 21-9
2y = 12
2y/2 = 12/2
y =6