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2 years ago

If Y is directly proportional to X² and y=21 when x=2, find the value of y when X=4.

Mathematics

2 answers:

kykrilka [37]2 years ago

8 0

Step-by-step explanation:

it means y/x^2=k

when y=21, x=2; k is 21/4.

when x=4, k is y/16.

k=21/4=y/16.

the next step is easy to see, you can do it.

frozen [14]2 years ago

7 0

The value of y will probably be 4.

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Step-by-step explanation:

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2 years ago

Read 2 more answers

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ehidna [41]

Using SOH CAH TOA

Sin =opposite/hypotenuse

that means opposite=2

Hypotenuse=3

Cos=Adjacent/Hypotenuse

Using Pythagorean theorem

Hyp^2=Opp^2 +Adj^2

3^2 =2^2+adj^2

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9-4=adj^2

5=adj^2

Taking the square root of both sides

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Step-by-step explanation:

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