How do you solve $x^2 – 10x – 1 = -10$ using the quadratic formula?

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Answer 1 · 2017-08-14T04:12:34

$x=9,1$

Given:

$x^2-10x-1=-10$

Move all terms to the left side.

$x^2-10x-1+10=0$

Simplify.

$x^2-10x+9$ $larr$ Quadratic equation in standard form:

$ax^2+bx+c=0$ , where:

$a=1$ , $b=-10$ , and $c=9$ .

$x=(-b+-sqrt(b^2-4ac))/(2a)$

Substitute the given values into the formula.

$x=(-(-10)+-sqrt((-10)^2-4*1*9))/(2*1)$

Simplify.

$x=10+-sqrt(100-36))/2$

Simplify.

$x=(10+-sqrt64)/2$

$x=(10+-8)/2$

Solutions for $x$ .

$x=(10+8)/2,$ $(10-8)/2$

Simplify.

$x=18/2,$ $2/2$

$x=9,1$

How do you solve x^2 – 10x – 1 = -10x^2 – 10x – 1 = -10 using the quadratic formula?