If x varies inversely as y, and x = 3 when y= 8, find y when x=4

Mathematics

1 answer:

gladu [14]4 years ago

6 0

The value of y is 6 when x is 4

Step-by-step explanation:

If x varies inversely as y, then

x = $\frac{k}{y}$ , where k is the constant of variation
xy = k, you can find k by using the initial values of x and y
$\frac{x_{1}}{x_{2}}=\frac{y_{2}}{y_{1}}$

∵ x varies inversely as y

∴ x = $\frac{k}{y}$

∵ When x = 3, y = 8

- Substitute these values in the equation to find k

∴ 3 = $\frac{k}{8}$

- Multiply both sides by 8

∴ 24 = k

∴ The equation of variation is x = $\frac{24}{y}$

∵ x = 4

- Substitute the value of x in the equation to find y

∴ 4 = $\frac{24}{y}$

- Multiply both sides by y

∴ 4y = 24

- Divide both sides by 4

∴ y = 6

The value of y is 6 when x is 4

Learn more:

You can learn more about the direct and inverse variation in brainly.com/question/10708697

#LearnwithBrainy

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