SOLUTION: Solve equation for x using quadratic formula 4x^2+5x-2=0 If there is more than one solution, seperate with commas

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Question 160437: Solve equation for x using quadratic formula
4x^2+5x-2=0
If there is more than one solution, seperate with commas
Found 2 solutions by jim_thompson5910, checkley77:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

4x%5E2%2B5x-2=0 Start with the given equation.


Notice we have a quadratic equation in the form of ax%5E2%2Bbx%2Bc where a=4, b=5, and c=-2


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-%285%29+%2B-+sqrt%28+%285%29%5E2-4%284%29%28-2%29+%29%29%2F%282%284%29%29 Plug in a=4, b=5, and c=-2


x+=+%28-5+%2B-+sqrt%28+25-4%284%29%28-2%29+%29%29%2F%282%284%29%29 Square 5 to get 25.


x+=+%28-5+%2B-+sqrt%28+25--32+%29%29%2F%282%284%29%29 Multiply 4%284%29%28-2%29 to get -32


x+=+%28-5+%2B-+sqrt%28+25%2B32+%29%29%2F%282%284%29%29 Rewrite sqrt%2825--32%29 as sqrt%2825%2B32%29


x+=+%28-5+%2B-+sqrt%28+57+%29%29%2F%282%284%29%29 Add 25 to 32 to get 57


x+=+%28-5+%2B-+sqrt%28+57+%29%29%2F%288%29 Multiply 2 and 4 to get 8.


x+=+%28-5%2Bsqrt%2857%29%29%2F%288%29 or x+=+%28-5-sqrt%2857%29%29%2F%288%29 Break up the expression.


So the answers are x+=+%28-5%2Bsqrt%2857%29%29%2F%288%29 or x+=+%28-5-sqrt%2857%29%29%2F%288%29


which approximate to x=0.319 or x=-1.569

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
4X^2+5X-2=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
X=(-5+-SQRT[5^2-4*4*-2])/2*4
X=(-5+-SQRT[25+32])/8
X=(-5+-SQRT57)/8
X=(-5+-7.599)/8
X=(-5+7.599)/8
X=2.5499/8
X=.3187 ANSWER.
X=(-5-7.5499)/8
X=-12.5499/8
X=-1.569 ANSWER.