x-4y=66 and y=3x
how do you solve that
Using the second equation, substitute the value
of y into the first equation.
x - 4y = 66
x - 4(3x) = 66
x - 12x = 66
-11x = 66
-11x / -11 = 66 / -11
x = -6
Plug that into the second equation.
y = 3x
y = 3(-6)
y = -18
x = -6 and y = -18