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4 votes
Y varies directly as x If x = 2 then y = 6. Find y when x = 7.

2 Answers

3 votes
i believe the answe is 21 because the difference between x and y is 3x
User Fernando Vellozo
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5.4k points
7 votes

Since the variation is generic, then we have an equation of the form:


y = kx

Where,

k: proportionality constant.

We must find the value of k.

For this, we use the following data:

x = 2 then y = 6

We have then:


6 = k2

Clearing k we have:


k = (6)/(2)


k = 3

Then, the equation is:


y = 3x

Substituting for x = 7 we have:


y = 3 (7)


y = 21

Answer:

The value of y for x = 7 is:


y = 21

User Gianfranco
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5.1k points