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elizabeth
10-19-2013, 07:03 PM
The sum of two numbers is 14 and their product is 40. What is the value of the sum of their squares?

(A) 116
(B) 126
(C) 196
(D) 206

Thanks!!

kadence
10-19-2013, 07:04 PM
From the following identity we have that

a^2+b^2=(a+b)^2-2ab=(14)^2-2(40)=196-80=116

Therefore the correct answer is (A).

kadence
10-19-2013, 07:04 PM
Thank you kadence!