Before using elimination, get rid of the fractions by 
multiplying them through by the least common denominator of 4:





We notice that the y terms will cancel if we multiply the second 
equation through by 8 to make the +3y become +24y. then it will
cancel with the -24y term in the first equation:


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Finish by subtituting 8 for x in any of the above equations
which contain both letters.  I'll pick this one







The solution is (x,y) = (8,12)

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b.) 

Multiply the first one through by 4





Now we need to line the terms up su that the x terms come first,
the y-terms come second, the equal signs come third and the constant
terms come fourth.  We do that by adding and subtracting terms from
both sides until they get like this:



We notice that the x terms will cancel if we multiply the first 
equation through by -2 to make the x become -2x. Then it will
cancel with the 2x term in the second equation:


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Finish by subtituting 16 for y in any of the above equations
which contain both letters.  I'll pick this one







The solution is (x,y) = (-2,16)

Edwin