Question

Y is directly proportional to x.y is 30 and x is 6 work out the equation linking x and y

Answer 1

y = 5x

Explanation:

Given that y is directly proportional to x then the equation relating them is

y = kx ← k is the constant of proportionality

To find k use the condition that y = 30 when x = 6

k =
`(y)/(x)` =
`(30)/(6)` = 5

y = 5x ← equation of proportion