Question

How do I use y=mx to solve this?​

Answer 1

see explanation

Explanation:

let m be mars and e be earth.

Given that m varies directly with e then the equation relating them is

m = ke ← k is the constant of variation

To find k use the condition m = 50, e = 150, then

k =
`(m)/(e)` =
`(50)/(150)` =
`(1)/(3)`

m =
`(1)/(3)` e ← equation of variation

When e = 120, then

m =
`(1)/(3)` × 120 = 40 pounds