Question

Subtract the following rational expressions


`(8k)/(9k - 4) - (3k^3)/(2k + 7)`
please show all work​

Answer 1

-27k^4 +12k^3+16k^2+56k

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(9k-4)(2k+7)

Explanation:

8k 3k^3

--------- - -----------

9k-4 2k+7

Get a common denominator

8k *(2k+7) 3k^3 *(9k-4)

--------- - -----------

(9k-4)(2k+7) (9k-4)(2k+7)

Combine

8k *(2k+7) -3k^3 *(9k-4)

---------------------

(9k-4)(2k+7)

Distribute

16k^2+56k -27k^4 +12k^3

---------------------

(9k-4)(2k+7)

-27k^4 +12k^3+16k^2+56k

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(9k-4)(2k+7)