SOLUTION: How can I solve 3x+2y=5 & x-2y=4 by using elimination method?

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Question 626003: How can I solve 3x+2y=5 & x-2y=4 by using elimination method?
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
system%283x%2B2y=5%2C++1x-2y=4%29

Add corresponding terms, using the principle 

"Equals added to equals give equals"

system%283x%2B2y=5%2C++1x-2y=4%2C%22_________%22%29
 system%284x%2B0y=9%29 <- Notice that the y terms were eliminated.
 
    4x = 9
     x = 9%2F4

Now let's eliminate the x-terms.  To do that we have to make the
x-terms cancel out like the y-terms did in the first case.

system%283x%2B2y=5%2C++1x-2y=4%29

Let's multiply the second equation through by -3 so that the 1x
will become -3x and will cancel with the 3x in the first
equation:



system%28%22%22%2B3x%2B2y=5%2C++-3x%2B6y=-12%2C%22_________%22%29
 system%28%22%22%2B0x%2B8y=-7%29 <- Notice that the x terms were eliminated.
 
    8y = -7
     y = %28-7%29%2F8
     y = -7%2F8

Solution: If the lines were graphed they would intersect at

the point (9%2F4,-7%2F8)
     
Edwin