SOLUTION: how do you solve for y=x+6 and y=-2x please

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Question 1170943: how do you solve for y=x+6 and y=-2x please
Found 2 solutions by MathLover1, MathTherapy:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

y=x%2B6......eq.1
y=-2x......eq.2
-------------------------
substitute y from eq.2 in eq.1

-2x=x%2B6......eq.1, solve for x
-2x%2B2x=x%2B2x%2B6
0=3x%2B6
0-6=3x%2B6-6
-6=3x
-6%2F3=x
x=-2
go to eq.2
y=-2x......eq.2, substitute x
y=-2%28-2%29
y=4




Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

how do you solve for y=x+6 and y=-2x please
y = x + 6 ----- eq (i)

y = - 2x ------ eq (ii)

- 2x = x + 6 ------ Substituting - 2x for y in eq (i)

- 2x - x = 6

- 3x = 6

highlight_green%28matrix%281%2C5%2C+x%2C+%22=%22%2C+6%2F%28-+3%29%2C+%22=%22%2C+-+2%29%29

y = - 2 + 6 ------ Substituting - 2 for x in eq (i)

highlight_green%28matrix%281%2C3%2C+y%2C+%22=%22%2C+4%29%29