SOLUTION: Missing ages. Molly�s age is twice Anita�s. If the sum of the squares of their ages is 80, then what are their ages? I started this problem and took 80 divided by two which gav

Question 289102: Missing ages. Molly�s age is twice Anita�s. If the sum of
the squares of their ages is 80, then what are their ages?
I started this problem and took 80 divided by two which gave me 40, then this is where i got stuck. Am i doing this right ro do i need to go about it differently?
Found 2 solutions by stanbon, Stitch:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Missing ages. Molly�s age is twice Anita�s. If the sum of
the squares of their ages is 80, then what are their ages?
-----------------------------------
Equations:
m = 2a
m^2 + a^2 = 80
----
Substitute for "m" and solve for "a":
(2a)^2 + a^2 = 80
4a^2 + a^2 = 80
5a^2 = 80
a^2 = 16
a = 4 (Anita's age)
---
Since m = 2a, m = 8 (Molly's age)
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Cheers,
Stan H.
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Answer by Stitch(470) (Show Source): You can put this solution on YOUR website!
Since you are dealing with squared numbers, you can not simply divide 80 by 2
--------------
Set-Up:
-------
Let Molly's age = A
Let Anita's age = B
Equation 1:
Equation 2:
--------------
Solution:
-------
Substitute the 2B from equation 1 into equation 2 for A
Equation 2:
Rewrite the equation
Simplify
Simplify
Divide both sides by 5
Take the square root of both sides

Now plug 4 into equation 1 for B
Equation 1:

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