SOLUTION: (x^2-2x-3=0)

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Question 174580: (x^2-2x-3=0)
Found 2 solutions by jim_thompson5910, tutorcecilia:
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


Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-2x-3=0
(x-3)(x+1)=0 [factor]
x-3=0 [set each factor equal to zero and solve for the x-value]
x=3
and
x+1=0
x=-1
So, the solutions are x = 3 and x = -1