Answer:
(4, 7) (third answer choice)
Step-by-step explanation:
In the system
y = x + 3
3x + y = 19
the first equation already gives y in terms of x. Thus we can substitute x + 3 for y in the second equation:
3x + (x + 3) = 19, which simplifies to:
4x = 16, yielding x = 4. Substituting 4 for x in the first equation, we get:
y = (4) + 3 = 7.
Thus, the solution is (4, 7) (third answer choice).
