2002 AMC 10B Problem 10

Suppose that a and b are nonzero real numbers, and that the equation x^2+ax+b=0 has solutions a and b. What is the pair (a,b)?

\mathrm{(A) \ } (-2,1)\qquad \mathrm{(B) \ } (-1,2)\qquad \mathrm{(C) \ } (1,-2)\qquad \mathrm{(D) \ } (2,-1)\qquad \mathrm{(E) \ } (4,4)

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