SOLUTION: -x^2-3x+5=0

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Question 375827: -x^2-3x+5=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-x%5E2-3x%2B5=0 Start with the given equation.


x%5E2%2B3x-5=0 Multiply EVERY term by -1 to make the leading coefficient positive.


Notice that the quadratic x%5E2%2B3x-5 is in the form of Ax%5E2%2BBx%2BC where A=1, B=3, and C=-5


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-%283%29+%2B-+sqrt%28+%283%29%5E2-4%281%29%28-5%29+%29%29%2F%282%281%29%29 Plug in A=1, B=3, and C=-5


x+=+%28-3+%2B-+sqrt%28+9-4%281%29%28-5%29+%29%29%2F%282%281%29%29 Square 3 to get 9.


x+=+%28-3+%2B-+sqrt%28+9--20+%29%29%2F%282%281%29%29 Multiply 4%281%29%28-5%29 to get -20


x+=+%28-3+%2B-+sqrt%28+9%2B20+%29%29%2F%282%281%29%29 Rewrite sqrt%289--20%29 as sqrt%289%2B20%29


x+=+%28-3+%2B-+sqrt%28+29+%29%29%2F%282%281%29%29 Add 9 to 20 to get 29


x+=+%28-3+%2B-+sqrt%28+29+%29%29%2F%282%29 Multiply 2 and 1 to get 2.


x+=+%28-3%2Bsqrt%2829%29%29%2F%282%29 or x+=+%28-3-sqrt%2829%29%29%2F%282%29 Break up the expression.


So the solutions are x+=+%28-3%2Bsqrt%2829%29%29%2F%282%29 or x+=+%28-3-sqrt%2829%29%29%2F%282%29


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim