SOLUTION: What is the discriminant of x^2 + 6x + 9 = 0 and x^2 + 2x - 8 = 0. What can you conclude about the type of solutions in each case?

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Question 733309: What is the discriminant of x^2 + 6x + 9 = 0 and x^2 + 2x - 8 = 0. What can you conclude about the type of solutions in each case?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The discriminant is +b%5E2+-+4a%2Ac+ in the
quadratic formula x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
+x%5E2+%2B+6x+%2B+9+=+0+
+a+=+1+
+b+=+6+
+c+=+9+
+b%5E2+-+4a%2Ac+=+6%5E2+-+4%2A1%2A9+
+b%5E2+-+4a%2Ac+=+36+-+36+
+36+-+36+=+0+
When the discriminant is +0+, there is
a single real solution ( called a double root )
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+x%5E2+%2B+2x+-+8+=+0+
+a+=+1+
+b+=+2+
+c+=+-8+
+b%5E2+-+4a%2Ac+=+4+-+4%2A1%2A%28-8%29+
+b%5E2+-+4a%2Ac+=+4+%2B+32+
+b%5E2+-+4a%2Ac+=+36+
The discriminant is positive, so there
are 2 real solutions
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Here are plots of both equations:
+graph%28+400%2C+400%2C+-10%2C+10%2C+-10%2C+10%2C+x%5E2+%2B+6x%2B+9%2C+x%5E2+%2B+2x+-+8+%29+