SOLUTION: solve 3x² + x - 2

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Question 947603: solve 3x² + x - 2
Found 3 solutions by rfer, josmiceli, Alan3354:
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
a=3
b=1
c=-2
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sqrt(1-4*3*-2)
=sqrt25
=5
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(-1+5)/6=
4/6=2/3
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(-1-5)/6=-1
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(0,2/3)
(0,-1)

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+3x%5E2+%2B+x+-+2+
Use quadratic formula
+x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+
+a+=+3+
+b+=+1+
+c+=+-2+
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+x+=+%28+-1+%2B-+sqrt%28+1%5E2+-+4%2A3%2A%28-2%29+%29%29+%2F+%282%2A3%29+
+x+=+%28+-1+%2B-+sqrt%28+1+%2B+24%29%29+%2F+6+
+x+=+%28+-1+%2B-+sqrt%28+25%29%29+%2F+6+
+x+=+%28+-1+%2B+5+%29+%2F+6+
+x+=+4%2F6+
+x+=+2%2F3+
and, using the negative square root,
+x+=+%28+-1+-+5+%29+%2F+6+
+x+=+-6%2F6+
+x+=+-1+
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check:
The factors are:
+%28+x+-+2%2F3+%29%2A%28+x+%2B+1+%29+=+0+
+x%5E2+%2B+%281%2F3%29%2Ax+-+2%2F3+=+0+
Multiply both sides by +3+
+3x%5E2+%2B+x+-+2+=+0+
OK

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Equations are solved.
This is not an equation, there's no equal sign.
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solve 3x² + x - 2 = 0 is a possibility.
solve 3x² + x - 2 = pi is another
solve 3x² + x - 2 = -10000000 is another.
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You have to spec what's the polynomial is equal to.
Why the other tutors assumed zero (0) is a mystery.