Answer
$(7x-8)^2(121-56x)$
Work Step by Step
Take out the common factor $(7x-8)^2$, we have $(5-2x)(3)(7x-8)^2(7)+(7x-8)^3(-2)=(7x-8)^2(21(5-2x)-2(7x-8))=(7x-8)^2(105-42x-14x+16)=(7x-8)^2(121-56x)$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.