SOLUTION: HELP!!! Solve the equation algebraically by factoring or using quadratic formula; x squared - 2x -3 = 0 very confused!!!!!

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Question 153243: HELP!!!
Solve the equation algebraically by factoring or using quadratic formula;
x squared - 2x -3 = 0
very confused!!!!!
Found 3 solutions by stanbon, Earlsdon, jim_thompson5910:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation algebraically by factoring or using quadratic formula;
x squared - 2x -3 = 0
---------------
x^2-2x-3 = 0
(x-3)(x+1) = 0
x = 3 or x=-1
==================
Cheers,
Stan H.

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x:
x%5E2-2x-3+=+0 Factor the trinomial.
%28x-3%29%28x%2B1%29+=+0 Apply the zero product rule.
x-3+=+0 or x%2B1+=+0
x+=+3 or x+=+-1

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E2-2x-3=0 Start with the given equation.


Notice we have a quadratic equation in the form of ax%5E2%2Bbx%2Bc where a=1, b=-2, and c=-3


Let's use the quadratic formula to solve for x


x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29 Start with the quadratic formula


x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-3%29+%29%29%2F%282%281%29%29 Plug in a=1, b=-2, and c=-3


x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-3%29+%29%29%2F%282%281%29%29 Negate -2 to get 2.


x+=+%282+%2B-+sqrt%28+4-4%281%29%28-3%29+%29%29%2F%282%281%29%29 Square -2 to get 4.


x+=+%282+%2B-+sqrt%28+4--12+%29%29%2F%282%281%29%29 Multiply 4%281%29%28-3%29 to get -12


x+=+%282+%2B-+sqrt%28+4%2B12+%29%29%2F%282%281%29%29 Rewrite sqrt%284--12%29 as sqrt%284%2B12%29


x+=+%282+%2B-+sqrt%28+16+%29%29%2F%282%281%29%29 Add 4 to 12 to get 16


x+=+%282+%2B-+sqrt%28+16+%29%29%2F%282%29 Multiply 2 and 1 to get 2.


x+=+%282+%2B-+4%29%2F%282%29 Take the square root of 16 to get 4.


x+=+%282+%2B+4%29%2F%282%29 or x+=+%282+-+4%29%2F%282%29 Break up the expression.


x+=+%286%29%2F%282%29 or x+=++%28-2%29%2F%282%29 Combine like terms.


x+=+3 or x+=+-1 Simplify.


So the answers are x+=+3 or x+=+-1