SOLUTION: please help me solve this eqation 2x^2+11+5

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Question 170019: please help me solve this eqation 2x^2+11+5
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Are you sure that the equation is not 2x%5E2%2B11x%2B5=0??


If so, then...


2x%5E2%2B11x%2B5=0 Start with the given equation.


Notice we have a quadratic equation in the form of ax%5E2%2Bbx%2Bc where a=2, b=11, 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-%2811%29+%2B-+sqrt%28+%2811%29%5E2-4%282%29%285%29+%29%29%2F%282%282%29%29 Plug in a=2, b=11, and c=5


x+=+%28-11+%2B-+sqrt%28+121-4%282%29%285%29+%29%29%2F%282%282%29%29 Square 11 to get 121.


x+=+%28-11+%2B-+sqrt%28+121-40+%29%29%2F%282%282%29%29 Multiply 4%282%29%285%29 to get 40


x+=+%28-11+%2B-+sqrt%28+81+%29%29%2F%282%282%29%29 Subtract 40 from 121 to get 81


x+=+%28-11+%2B-+sqrt%28+81+%29%29%2F%284%29 Multiply 2 and 2 to get 4.


x+=+%28-11+%2B-+9%29%2F%284%29 Take the square root of 81 to get 9.


x+=+%28-11+%2B+9%29%2F%284%29 or x+=+%28-11+-+9%29%2F%284%29 Break up the expression.


x+=+%28-2%29%2F%284%29 or x+=++%28-20%29%2F%284%29 Combine like terms.


x+=+-1%2F2 or x+=+-5 Simplify.


So the answers are x+=+-1%2F2 or x+=+-5