SOLUTION: solve for x using the quadratic formula {{{3x^2=5x+6}}} Please explain the steps for me...thanx a bunch

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Question 91593: solve for x using the quadratic formula 3x%5E2=5x%2B6
Please explain the steps for me...thanx a bunch

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x using the quadratic formula 3x^2 = 5x + 6
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Put the equation in the ax^2 + bx + 3 = 0 form
3x^2 - 5x - 6 = 0; subtracted 5x and 6 from both sides
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The quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
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In your equation: a = 3; b = -5; c = -6, substitute in the formula:
x+=+%28-%28-5%29+%2B-+sqrt%28-5%5E2+-+4+%2A+3+%2A+-6+%29%29%2F%282%2A3%29+
:
x+=+%28%2B5+%2B-+sqrt%2825+-+%28-72%29+%29%29%2F%286%29+
:
x+=+%28%2B5+%2B-+sqrt%2825+%2B+72%29+%29%2F%286%29+; minus a minus is a plus
:
x+=+%28%2B5+%2B-+sqrt%2897%29+%29%2F%286%29+
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1st solution:
x+=+%28%2B5+%2B9.849+%29%2F%286%29+; found the square root of 97
x+=+14.849%2F6
x = +2.475
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2nd solution
x+=+%28%2B5+-+9.849+%29%2F%286%29+
x+=+-4.849%2F6
x = -.808
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Did you understand each step here?
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It's a good idea to substitute at least one of the solutions in the original equation. Try x = 2.475
3x^2 = 5x + 6
3(2.475^2) = 5(2.475) + 6
3(6.126) = 12.375 + 6
18.378 = 18.375; close enough to confirm out solution
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You can check the -.808 solution the same way
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If you have any questions, you can email me until 9 PM, central