Question 123845: I do not get how to use the substitution method while solving the equation 2x+4y=-6
x-3y=7
Answer by chitra(359)  (Show Source):
You can put this solution on YOUR website! The given equations are:
2x + 4y = -6 ------------------(1)
x - 3y = 7 --------------------(2)
The 2nd equation can be re-written as: x = 3y + 7 --------(3)
Substituting the 3rd eqn in the first equation we get:
2(3y + 7) + 4y = - 6
using distributive property,
6y + 14 + 4y = - 6
10y + 14 = - 6
10y = -6 - 14
10y = -20
==> y = 
==> y = - 2
Now by back substitution,in equation(3) we get:
x = 3y + 7
x = 3(-2) + 7
x = -6 + 7
x = 1
thus the solution.
regs
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