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Part 1
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.
y = 7 when x = 6
Write a direct variation equation that relates x and y.
y = [ ] (Simplify your answer.)
To write a direct variation equation that relates x and y, we can use the formula:
y = kx
where k is the constant of variation.
Since we are given that y = 7 when x = 6, we can substitute these values into the equation to find k:
7 = k(6)
To find the value of k, we can solve for it:
k = 7/6
Now that we have the value of k, we can write the direct variation equation:
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)
y = 21