Answer:
x = 1/2 y = -5/2
Step-by-step explanation:
Since we already know an equation for y, we just need to plug it into the other equation.
21x - 7(-5x) = 28
21x + 35x = 28
56x = 28
x = 1/2
Now that we know x, we substitute it into the other equation, to find y.
y = -5x
y = -5(1/2)
= -5/2
