SOLUTION: I think i did this problem right, but it still seems wrong. Question: 7a/15b^2 + b/18ab What I have done: 42a^2/90ab^2+ 5b^2/90ab^2 =47a^2b^2/90ab^2=47a/90

Question 21838: I think i did this problem right, but it still seems wrong.
Question: 7a/15b^2 + b/18ab
What I have done: 42a^2/90ab^2+ 5b^2/90ab^2
=47a^2b^2/90ab^2=47a/90

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
When you have the common denominator of 90ab^2 as the
denominator of your two fractions (which you did
correctly) your next step is to add the numerators
of the two fractions and write that sum over the common
denominator, as follows:
[42a^2+5b^2)/[90ab^2]
That is as far as you can go because you have on
"like" terms in the numerator and no common factor.
You cannot add the 42 and the 5 because the terms
are not "like"---it is like 42 apples and 5 oranges,
which cannot be added.
Cheers,
Stan H.
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