Apassenger plane made a trip to las vegas and back. on the trip there it flew 432 mph and on return trip it went 40 mph. how long did the trip there take if the return trip took nine hours?

the answer is a if my teacher taught me correct

this is a direct variation proportion. y = kx

y is the total amount due, k is the constant of variation, and x is the number of texts sent.

plug in the 3.20 and the 16 to solve for the "k". this is the constant of proportionality. it is the value that will not change.

3.20 = k(16). solving you get $.20 per text.

the equation would then be y = .20x