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Solve x2 - 8x = 3 by completing the square. Which is the solution set

[4 - 19,4 + /19}
{4 - V11, 4 + /11)
{4 - V8, 4 + }
[4 - V3, 4 + (3)

User Yoonju
by
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1 Answer

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Answer:

4\pm\sqrt{19}

Explanation:

Move everything to left side


x^(2) -8x -3 =0

Now to solve this square equation we need to find Descriminant


D=b^(2) -4ac=64+12=76

As Descriminant D is greater than 0 then we have 2 solutions which we can calculate by this formula


x_(1,2)=(-b\pm√(D))/(2a) =(8\pm2√(19))/(2)=4\pm√(19)

User Colin T Bowers
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8.3k points