SOLUTION: Find all real solutions of the equation. 7x^2+14x-5=0

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Question 1037594: Find all real solutions of the equation. 7x^2+14x-5=0
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
There can be 0, 1, or 2 real solution
If the discriminant +b%5E2+-+4%2Aa%2Ac+ is positive,
then the solutions are real
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+a+=+7+
+b+=+14+
+c+=+-5+
+b%5E2+-+4%2Aa%2Ac+=+14%5E2+-+4%2A7%2A%28-5%29+
+b%5E2+-+4%2Aa%2Ac+=+196+%2B+140+
+b%5E2+-+4%2Aa%2Ac+=+336+
The solutions are real
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Use the quadratic formula:
+x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
+x+=+%28-14+%2B-+sqrt%28+14%5E2-4%2A7%2A%28-5%29+%29%29%2F%282%2A7%29+
+x+=+%28-14+%2B-+sqrt%28+336+%29%29%2F14+
+x+=+%28+-14+%2B+18.3303+%29+%2F+14+
+x+=+4.3303+%2F+14+
+x+=+.3093+
and
+x+=+%28+-14+-+18.3303+%29+%2F+14+
+x+=+-32.3303+%2F+14+
+x+=+-2.3093+
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Here's the plot:
+graph%28+400%2C+400%2C+-5%2C+5%2C+-15%2C+15%2C+7x%5E2+%2B+14x+-+5+%29+