sarah,
student highschool level

how is this problem solved??

3/ x+1 - 5/x
( 3 divided by x +1 subtracted by 5 divided by x)

Hi Sarah,

You solve this problem just as you would solve 3/7 - 5/9. You first need to find a common denominator. With 3/7 - 5/9 the common denominator is 7 times 9. Thus multiply the numerator and denominator of the first fraction by 9 and multiply the numerator and denominator of the second fraction by 7 to get

3/7 - 5/9 = 3(9)/7(9) - 5(7)/9(7)
= 27/63 - 35/63 = (27 - 35)/63 = -8/63.

Likewise for the algebraic fractions. The common denominator of 3/(x + 1) and 5/x is (x + 1) times x. Thus multiply the numerator and denominator of the first fraction by x and multiply the numerator and denominator of the second fraction by (x + 1) to get

Cheers,
Penny
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