Answer:
The solution of this system is (9, 2).
Explanation:
Substitute x - 7 for 'y' in the first equation. We get:
x - 3(x - 7) = 3 Doing this temporarily eliminates the variable 'y'.
Now perform the indicated multiplication, and then combine like terms:
x - 3x + 21 = 3, or
-2x = -18
so that x = 9. Substituting 9 for x in the second equation, we get:
y = 9 - 7, or y = 2.
The solution of this system is (9, 2).