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Jobisdone [24]
3 years ago
6

John is twice as old as Mary. The sum of their ages is 21. How old is Mary?

Mathematics
1 answer:
Nitella [24]3 years ago
8 0

Answer:

Mary is 7

Because 14+7 =21

So j+m=21

J - 2m= 0

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Double angle identity for sine:

\sin(2x) = 2 \sin(x) \cos(x)

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Factorize the left side.

2 \sin(\theta) - 2 \sin(\theta) \cos^2(\theta) = 2 \sin(\theta) \left(1 - \cos^2(\theta)\right)

Pythagorean identity:

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so that

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Step-by-step explanation:

Given

12x³ - 9x² + 4x - 3 ( factor the first/second and third/fourth terms )

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2 is the answer you need
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Answer:

Hey there!

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If Mrs. Williams has 1/4 gallon of juice, 1/4 divided by 5 = 1/20.

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