SOLUTION: Write a formula that expresses the relationship described below. y varies directly as x and y = 7 when x = 2.

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Question 149147: Write a formula that expresses the relationship described below.
y varies directly as x and y = 7 when x = 2.

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Write a formula that expresses the relationship described below.
y varies directly as x and y = 7 when x = 2.
.
If something varies "directly" we have the following relationship:
y = kx
where k is a constant
.
Since the problem gave you x and y, plug it in and solve for k:
y = kx
7 = k(2)
k = 7/2
.
Your formula is therefore:
y = (7/2)x