SOLUTION: find the x-intercepts of the following equation -2xsquare+12x-10

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Question 743521: find the x-intercepts of the following equation -2xsquare+12x-10
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
I can say:
+f%28x%29+=+-2x%5E2+%2B+12x+-+10+
Then set +f%28x%29+=+0+ to find the roots, or
x-intercepts
+-2x%5E2+%2B+12x+-+10+=+0+
Divide both sides by +2+
+-x%5E2+%2B+6x+-+5+=+0+
I can find roots with quadratic formula
+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+
+a+=+-1+
+b+=+6+
+c+=+-5+
+x+=+%28-6+%2B-+sqrt%28+6%5E2+-+4%2A%28-1%29%2A%28-5%29+%29%29+%2F+%282%2A%28-1%29%29+
+x+=+%28-6+%2B-+sqrt%28+36+-+20+%29%29+%2F+%28-2%29%29+
+x+=+%28-6+%2B-+sqrt%28+16+%29%29+%2F+%28-2%29%29+
+x+=+%28+-6+%2B+4+%29+%2F+%28-2%29+
+x+=+1+
and, also,
+x+=+%28+-6+-+4+%29+%2F+%28-2%29+
+x+=+5+
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The x-intercepts are at +x+=+1+ and +x+=+5+
Here's the plot:
+graph%28+400%2C+400%2C+-3%2C+10%2C+-10%2C+6%2C+-x%5E2+%2B+6x+-+5+%29+