Question

15 POINTS!

m varies jointly as x and y, and m = 7 when x = 3 and y = 15 solve for m when x = 25 and y = 9. You may use k to represent the constant of variation in working if nesessary

Answer 1

m = 35

Explanation:

∵ m ∝ xy

∴ m = kxy

∵ m = 7 when x = 3 and y = 15

∴ 7 = k (3) (15)

∴ 7 = 45k ⇒ ∴ k = 7/45

∴ m = 7/45 xy

∵ x = 25 and y = 9

∴ m = (7/45) (25)(9) = 35