equations: solve 5x - y = -9 for y

[haliebre]

The system below is to be solved by substitution. Solve equation 2 for y.

2x + 3y =8
5x - y=-9

Is my answer then 5x + 9 = y?

 

[askmemath]

Yup that would be correct!

 

[Gene]

Correct as far as you went. You have to solve the first for x, substitute that in the second, (or vice-versa) THEN solve for y.
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Gene

 

[haliebre]

My choices for answers were:

a. y= -5x-9
b. y= 5x + 9
c. 5x - 9
d. -5x + 9

That is why I only went this far.

 

[Gene]

Oops, I missed the "equation 2 for y" part. The "solve by substitution" part fooled me completely.
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Gene