SOLUTION: x2-2x-13=0 i can not figure out how to figure this out

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Question 418439: x2-2x-13=0 i can not figure out how to figure this out
Found 2 solutions by stanbon, MathLover1:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
x^2-2x-13=0
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Use the quadratic formula:
x = [2 +- sqrt(4 -4*-13)]/2
----
x = [2 +- sqrt(56)]/2
----
x = [2 +- 2sqrt(14)]/2
---
x = [1 +- sqrt(14)]
=======================================
Cheers,
Stan H

Answer by MathLover1(20849) (Show Source):
You can put this solution on YOUR website!

Solved by pluggable solver: Quadratic Formula

Let's use the quadratic formula to solve for x:

Starting with the general quadratic

the general solution using the quadratic equation is:

So lets solve ( notice , , and )

Plug in a=1, b=-2, and c=-13

Negate -2 to get 2

Square -2 to get 4 (note: remember when you square -2, you must square the negative as well. This is because .)

Multiply to get

Combine like terms in the radicand (everything under the square root)

Simplify the square root (note: If you need help with simplifying the square root, check out this solver)

Multiply 2 and 1 to get 2

So now the expression breaks down into two parts

or

Now break up the fraction

or

Simplify

or

So the solutions are:

or

so, or