SOLUTION: solve the equation by use of the quadratic formula. 3x^2=2x+6

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Question 1121191: solve the equation by use of the quadratic formula.
3x^2=2x+6
Found 3 solutions by josmiceli, Boreal, ikleyn:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+3x%5E2+=+2x+%2B+6+
+3x%5E2+-2x+-+6+=+0+
+x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4a%2Ac+%29%29+%2F+2a+
+a+=+3+
+b+=+-2+
+c+=+-6+
—————————-
+x+=+%28+-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2+-+4%2A3%2A%28-6%29+%29%29+%2F+2%2A3+
+x+=+%28+2+%2B-+sqrt%28+4+%2B+72+%29+%29+%2F+6+
+x+=+%28+2+%2B-+sqrt%28+76+%29+%29+%2F+6+
+x+=+%28+1+%2B+sqrt%28+19+%29+%29+%2F+3+
and
+x+=+%28+1+-+sqrt%28+19+%29+%29+%2F+3+

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Rewrite as 3x^2-2x-6=0. This setting everything on one side equalling 0 must be done.
a=3 b= -2 c= -6
x=(1/6)(2+/- sqrt(4-4*3*-6)); sqrt term is sqrt (76), or 2 sqrt (19)
The 2s on the top cancel out part of the 6 below
x=(1/3)(1+/- sqrt(19))
This is about +1.7 and -1.1
graph%28300%2C300%2C-5%2C5%2C-10%2C10%2C3x%5E2-2x-6%29

Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
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If you have difficulties solving quadratic equations using quadratic formula, then you can learn how to do it from the lessons

    - Introduction into Quadratic Equations
    - PROOF of quadratic formula by completing the square

in this site.