If m varies directly with n and m=12 when n=3 what is the value of m when n=4?

Tina practice piano for 15 hours last month and 45 hours this month use multiplication to write a statement comparing me i was tina practice during the two months use addition to write a statement comparing the hours tina practice during the two months

If f(x)=2x-6 and g(x)=3x+9, find (f-g)(x)

Which of the following is the explicit rule for a geometric sequence defined a recursive formula of a -5a for which the first term is 23?