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3 years ago

If y varies inversely with x and y =5 when x=20 find x when y = -4

Mathematics

1 answer:

sweet-ann [11.9K]3 years ago

7 0

Answer:

x=-25

Step-by-step explanation:

Inverse variation

xy =k

We know x and y

20*5 =k

100 =k

So the formula is

x y = 100

We know y = -4

x (-4) = 100

Divide each side by -4

-4x/-4 = 100/-4

x = -25

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The volume of the cylinder is:
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where:
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Since <span>the cone fits exactly inside of the cylinder, they have the same radius and the height:
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Also:
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Now, let's write two volume formulas together:
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We can include V₂ into V₁:
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Read 2 more answers

If y varies inversely with x and y =5 when x=20 find x when y = -4​

If y varies inversely with x and y =5 when x=20 find x when y = -4