SOLUTION: Please help me solve this equation: {{{ x^2-2x-3=0 }}}. & HOW DID YHU SOLVE IT I DONT UNDERSTAND AT ALL ! :(

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Question 273257: Please help me solve this equation: .
& HOW DID YHU SOLVE IT I DONT UNDERSTAND AT ALL ! :(

Answer by jim_thompson5910(35256)   (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=-3




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


Lets look at the first part:





Add the terms in the numerator

Divide


So one answer is






Now lets look at the second part:





Subtract the terms in the numerator

Divide


So another answer is




So our solutions are:

or


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