SOLUTION: Please help solve this system by substitution method. y = -4x - 7 y = 3x

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Question 334822: Please help solve this system by substitution method.

y = -4x - 7
y = 3x

Answer by janakisubramanian(2) About Me  (Show Source):
You can put this solution on YOUR website!
y = -4x - 7 ---------(1)
y = 3x
Solution:
Substitute y = 3x in the first equation.
So, 3x = - 4x - 7
==> 3x + 4x = -7 {transposing -4x to LHS)
==> 7x = -7
==> x = -7/7
==> x = -1
So now y = 3x
= 3 (-1)
= -3
Thus x = -1 and y = -3.