SOLUTION: I am having touble getting this problem right, if you could please help and break down the steps, I get confused with fractions and dividing and multiplying them. Any help is appre

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Question 574330: I am having touble getting this problem right, if you could please help and break down the steps, I get confused with fractions and dividing and multiplying them. Any help is appreciated thank you.
Solve the system by the elimination method.
5x+2y=-11
7x-3y=19
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +5x%2B2y=-11+
(2) +7x-3y=19+
Multiply (1) by 3
Multiply (2) by 2
Then add the equations
(1) +15x%2B6y=-33+
(2) +14x-6y=38+
+29x+=+5+
+x+=+5%2F29+
Plug this back into either (1) or (2)
(2) +7%2A%285%2F29%29+-+3y=19+
Now multiply both sides by +29+
( I'll go slowly )
(2) +29%2A7%2A%285%2F29%29+-+29%2A3y=+29%2A19+
OK, now rewrite it this way:
(2) +%2829%2F29%29%2A7%2A5+-+87y+=+551+
Notice that +29%2F29+=+1+, so
(2) +35+-+87y+=+551+
Subtract 35 from both sides
(2) +-87y+=+516+
Divide both sides by -87
(2) +y+=+-516%2F87+
( It doesn't reduce any more )
-----------------------
Now I have to check the answers
I'll do it on my calculator with approximate decimals
+5%2F29+=+.172414+
+-516%2F87+=+-5.93103+
I can write:
(1) +5x%2B2y=-11+
(1) +5%2A.172414+%2B+2%2A%28-5.93103%29+=+-11+
(1) +.86207+-+11.86207+=+-11+
(1) +-11+=+-11+
Perfect! Usually there's a slight error due
to rounding off.
Now you can check the other equation the same way.