Question

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)

Answer 1

Answer:

4\pm\sqrt{19}

Step-by-step 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

$x_{1,2}=\frac{-b\pm\sqrt{D}}{2a} =\frac{8\pm2\sqrt{19}}{2}=4\pm\sqrt{19}$