If speakers are originally £40 and the discount is 10% what was the price paid

Which of these choices show a pair of equivalent expressions?

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

Solve this equation using substitution. {4x + y = −2} {4x + 6y = 44}