Solve the following system:

y = x + 3

3x + y = 19

O (7,4)

O (-4,7)

O (4,7)

O (4.-7)

(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).