Question

Solve x2 − 10x = −13.

A) 5 ± 2square root 3
B) 5 ± square root 38
C) 5 ± 2square root 2
D) 5 ± 3square root 2​

Answer 1

Answer:

B

Step-by-step explanation:

First, let's rearrange the given equation into something more recognizable. If we add 13 to both sides, we now have the polynomial $x^{2}-10x+13$. We can now use the quadratic formula to solve.

Remember that the quadratic formula is

$\frac{-b+/-\sqrt{b^{2}-4ac } }{2a}$

Substitute the numbers from the equation into the formula.

$\frac{-(-10)+/-\sqrt{(-10)^{2}-4(1)(13) } }{2(1)}$

Simplify:

$\frac{10+/-\sqrt{100-52} }{2}$

$\frac{10+/-\sqrt{48} }{2}$

Here, I'm going to assume that there was a mistype in option B because if we divide out the 2 we end up with $5+/-\sqrt{48}$.

Hope this helps!