SOLUTION: The average of two numbers a and b is C, and the product of a and b is D. What is then a^2 + b^2
(a) C^2- 2D (b) 2C^2- 2D (c) 4C^2- D (d) 2C^2- D (e) 4C^2- 2D
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-> SOLUTION: The average of two numbers a and b is C, and the product of a and b is D. What is then a^2 + b^2
(a) C^2- 2D (b) 2C^2- 2D (c) 4C^2- D (d) 2C^2- D (e) 4C^2- 2D
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Question 290686: The average of two numbers a and b is C, and the product of a and b is D. What is then a^2 + b^2
(a) C^2- 2D (b) 2C^2- 2D (c) 4C^2- D (d) 2C^2- D (e) 4C^2- 2D Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! The average of two numbers a and b is C, = c
a + b = 2c
:
and the product of a and b is D.
ab = d
:
What is then a^2 + b^2
:
We know (a+b)*(a+b) = a^2 + 2ab + b^2
then
2c * 2c = 4c^2 = a^2 + 2ab + b^2
we know
2ab = 2d, subtract this to get a^2 + b^2
therefore
a^2 + b^2 = 4c^2 - 2d
