SOLUTION: solve by completing the square show work for credit 2x^2+6x-2=0 please solve, thanks.

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Question 51340: solve by completing the square show work for credit
2x^2+6x-2=0
please solve, thanks.
Answer by darq(90) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2+6x-2=0
first eliminate (x^2)'s coefficient by dividing both sides with 2
x^2+3x-1=0

then take x's coefficient (3) divide it with 2 now you have one and a half 3%2F2. and take 3%2F2's square we have 9%2F4. so in order to have a perfect square we need to convert (-1) to 9%2F4. we will do it by adding 1 + 9%2F4 to each side which is equal to 13%2F4

x%5E2%2B3x%2B%289%2F4%29=13%2F4
(x+(3/2))^2=13/4
x%2B%283%2F2%29=+%2B-+sqrt+%2813%2F4%29
x=%28+%2B-+sqrt%2813%29+%2F2%29-%283%2F2%29
x=%28+%2B-+sqrt%2813%29+-3%29%2F2
now we will find two possible answers;

x=%28%2Bsqrt%2813%29-3%29%2F2
and
x=%28-sqrt%2813%29-3%29%2F2