Help me plz I can’t figure this out

Leo has b boxes of pencils. each box contains 6 pencils. he has a total of 42 pencils. the equation that represents this situation the value of b that makes the equation true the first one is b+6=42,6b=42,b=42+6,or 42b=6 the second one are 7,836 48

If the sales price of a dvd is $20 and the markup is 34%, what is the cost of the dvd?

F(x)=5/6x+3 which of the following is true