\(200^2 - 2(200)(199) + 199^2 =\)

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Re: \(200^2 - 2(200)(199) + 199^2 =\)

by DHRJ007 » Fri Oct 02, 2020 1:45 am
just use the property of (a+b)whole square.
(200-199)whole square =1


ans:C

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Gmat_mission wrote:
Fri Oct 02, 2020 12:57 am
\(200^2 - 2(200)(199) + 199^2 =\)

(A) \(-79,201\)
(B) \(-200\)
(C) \(1\)
(D) \(200\)
(E) \(79,999\)

Answer: C

Solution:

Letting x = 200 and y = 199, we have:

x^2 - 2xy + y^2 = (x - y)^2

Therefore, the result is (200 - 199)^2 = 1^2 = 1.

Answer: C

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