Question

If y varies directly with x, find the missing value below. (9, 36) and (x, -24) Then enter only your numerical answer (without units) below to check.

Answer 1

x = - 6

Step-by-step explanation:

Given y varies directly with x then the equation relating them is

y = kx ← k is the constant of variation

To find k use (9, 36), that is x = 9, y = 36

36 = 9k ( divide both sides by 9 )

4 = k

y = 4x ← equation of variation

Using (x, - 24 ), that is find x when y = - 24

- 24 = 4x ( divide both sides by 4 )

x = - 6

Answer 2

x = - 6

Explanation:

Given y varies directly with x then the equation relating them is

y = kx ← k is the constant of variation

To find k use (9, 36), that is x = 9, y = 36

36 = 9k ( divide both sides by 9 )

4 = k

y = 4x ← equation of variation

Using (x, - 24 ), that is find x when y = - 24

- 24 = 4x ( divide both sides by 4 )

x = - 6