SOLUTION: Molly's age is twice Anita's. If the sum of the square of their ages is 80, what are their ages?

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Question 216275: Molly's age is twice Anita's. If the sum of the square of their ages is 80, what are their ages?
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
Molly's age is twice Anita's. If the sum of the square of their ages is 80, what are their ages?

Step 1. Let x be Anita's age

Step 2. Let 2x be Molly's age since it's twice Anita's

Step 3. Then x%5E2%2B%282x%29%5E2=80 since the sum of the square of their ages is 80.

Step 4. Simplifying 5x%5E2=80 or x%5E2=16.

Step 5. Taking the square root to both sides of the equation yields x=4. Then 2x=8.

Check...4%5E2%2B8%5E2=16%2B64=80...which is a true statement

Step 6. ANSWER: Anita is 4 years old and Molly is 8 years old.

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J