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X^2-2x-3=0, solve by completing the square

User Armahg
by
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1 Answer

23 votes
23 votes

Answer:

3,-1

Explanation:

Given equation,


\longrightarrow x^2 -2x -3 = 0 \\


\longrightarrow x^2 - 2(1)(x) = 0 +3 \\


\longrightarrow x^2 -2(1)(x) + 1^2 = 3+1^2\\


\longrightarrow (x-1)^2 = 4 = 2^2 \\


\longrightarrow x -1 =\pm 2 \\


\longrightarrow x = 2+1 , -2+1\\


\longrightarrow \underline{\underline{\qquad x = 3 ,-1}}\\

User Rudy Bunel
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