Posted by **at a lost ** on Friday, March 8, 2013 at 9:23pm.

use substitution to solve system

-2x+y= -9

=5x+4y= -30

- math -
**Steve**, Friday, March 8, 2013 at 11:56pm
hmmm. you must really be confused; not only at a loss, but at a lost!

we see that

-2x+y = -9, so

y = 2x-9

now substitute that into the other equation:

5x+4(2x-9) = -30

13x = 6

x = 6/13

so, y=2x-9 = -105/13

The =5x+4y confuses me. If that was supposed to be -5x, then

-5x+4(2x-9) = -30

3x = 6

x=2

which seems like a better answer.

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