Question 93406
subtract as indicated express the results in simplest form 
5a - 12/a^2 - 8a + 15 - (3a - 2)/a^2 - 8a + 15
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The denominators are the same so subtract the numerators
and put the result over the common denominator:
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[5a-12-3a+2] / [a^2=8a+15]

= [2a-10] / [(a-5)(a-3)]

= [2(a-5)]/[(a_5)(a-3)]

= 2/(a-3)

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Cheers,
Stan H.