SOLUTION: how do you solve the equation X^2 +2x-3

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Question 172648: how do you solve the equation X^2 +2x-3
Found 2 solutions by jim_thompson5910, Alan3354:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
First of all, x%5E2%2B2x-3 is NOT an equation (as it has no equal sign). Are you trying to solve x%5E2%2B2x-3=0




x%5E2%2B2x-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-%282%29+%2B-+sqrt%28+%282%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+=+%28-2+%2B-+sqrt%28+4-4%281%29%28-3%29+%29%29%2F%282%281%29%29 Square 2 to get 4.


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


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


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


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


x+=+%28-2+%2B-+4%29%2F%282%29 Take the square root of 16 to get 4.


x+=+%28-2+%2B+4%29%2F%282%29 or x+=+%28-2+-+4%29%2F%282%29 Break up the expression.


x+=+%282%29%2F%282%29 or x+=++%28-6%29%2F%282%29 Combine like terms.


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


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


Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve the equation X^2 +2x-3
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There are several methods. 3, anyway. I'll assume it's equal to zero, tho it doesn't say that. An "equation" gets its name from the "equal" sign, something is equal to something else. x^2 +2x-3 is not an equation, it's an expression, specifically a trinomial.
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Anyway, assuming it's equal to zero:
One method is to factor it:
x^2 +2x-3 = 0
(x+3)*(x-1) = 0
If the product is zero, one or both have to be zero. Right?
If x+3 = 0, then x=-3
If x-1 = 0, then x=+1
x can't be both, so it's either -3, or it's +1.
Those are the possible answers.
x = 1
x = -3