MATH HELP!!!!! If y = 15 when x = 2, what is the value of x when y = 7?

Mathematics

1 answer:

Ede4ka [16]3 years ago

3 0

<u>Direct Variation:</u> $\frac{y}{x} = k$

$\frac{15}{2} = k$

when y = 7: $\frac{7}{x} = \frac{15}{2}$

14 = 15x

$\frac{14}{15} = x$

<u>Inverse variation:</u> y*x = k

15 * 2 = k

30 = k

when y = 7: 7 * x = 30

$x = \frac{30}{7}$

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