Answer :
Use substitution
Plug in -5x for y in the second equation
x + 3(-5x) = 28
x - 15x = 28
-14x = 28, x = -2
Now plug in -2 for x in first equation
Y = -5(-2) = 10
Solution: D. (-2, 10)
Plug in -5x for y in the second equation
x + 3(-5x) = 28
x - 15x = 28
-14x = 28, x = -2
Now plug in -2 for x in first equation
Y = -5(-2) = 10
Solution: D. (-2, 10)