Suppose y varies directly with x. Write a direct variation equation that relates x and y. Then find the value of y when x=18

Question

y= 7 when x= 6

Answer 1

The direct variation equation that relates x and y is y = kx, where k is the constant of variation.

To find the value of k, we can use the given information that y = 7 when x = 6. Substituting these values into the equation, we get:

7 = k(6)

Dividing both sides by 6, we obtain:

k = 7/6

So the direct variation equation that relates x and y is:

y = (7/6)x

To find the value of y when x = 18, we can substitute x = 18 into the equation:

y = (7/6)(18)

Simplifying, we get:

y = 21