We have this:
7/9z^3 + 1/21z^3
Our LCD is 63z^3.
We now divide the LCD by each denominator and then multiply the quotient by each numerator.
63z^3/9z^3 = 7
Then, 7 times 7 = 49
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Next fraction:
63z^3 divided by 21z^3 = 3
Then, 3 x 1 = 3
We now add the numerators and keep the LCD.
(49 + 3)/63z^2
Final answer: 52/63z^3
Done!
Add. Simplify if possible.
7/9z^3 + 1/21z^3
I came up with 49+3z/63z^3
Is this correct?
2 answers
Thanks Guido.