Answer:
-21/5 or -4.2
Step-by-step explanation:
y = 2x + 6
3y - x + 3 = 0
Substitute the value for y from the first equation into the second equation. Solve for x.
3y - x + 3 = 0
3(2x + 6) - x + 3= 0
6x + 18 - x + 3 = 0
5x + 18 + 3 = 0
5x + 21 = 0
5x + 21 - 21 = 0 - 21
5x = -21
x = -21/5 or -4.2