x-4y=66 and y=3x

how do you solve that
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1 Answer

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
by Level 11 User (78.4k points)

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