Which two expressions are equivalent? A. 7(3 + x) and 7∙ 3 + 3 ∙ x
B. 7 + 3 + x and (7 + 3) + x
C. 7 ∙ x ∙ 3 and 7(x + 3)
D. 7 ÷ (3 – x) and 7 ÷ (x – 3)

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5