SOLUTION: Solve the system by addition. <pre> –5x + 2y = 10 x – 3y = 11 <pre>

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Question 70248: Solve the system by addition.
	–5x + 2y = 10

	  x – 3y = 11 


 

Answer by jim_thompson5910(35256) About Me  (Show Source): 

You can put this solution on YOUR website!
 
	–5x + 2y = 10

	  x – 3y = 11 


Multiply the bottom equation by 5, this gives you 5x so it cancels with -5x




	–5x + 2y = 10

	 5(x – 3y = 11) 


it then becomes




	–5x + 2y = 10

	 5x –15y = 55 


Now individually add the terms 5x and -5x to get 0x. Then add 2y and -15y to get -13y, and finally 10 and 55 to get 65


	0x - 13y = 65 


Now you can solve for y


  +cross%28-13%2F-13%29y+=+65%2F-13 
Divide both sides by -13

So y=-5. Now solve for x by plugging in y.

-5x%2B2%28-5%29=10

-5x%2Bcross%28-10%2B10%29=10%2B10Add 10 to both sides

-5x=20Simplify

cross%28-5%2F-5%29x=%2820%2F-5%29Divide both sides by -5

x=-4

So x=-4 and y=-5