SOLUTION: Hi! May I have some help with this equation? Find all values of k that ensure that the given equation has exactly one solution. 8x2 + kx + 7 = 0

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Question 120096: Hi! May I have some help with this equation?
Find all values of k that ensure that the given equation has exactly one solution.
8x2 + kx + 7 = 0
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
This is a case where you use the quadratic equation and make
sure that the discriminant, which is b%5E2+-+4ac is zero
That guarantees that there is only one solution.
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
where equation is in the form ax%5E2+%2B+bx+%2B+c+=+0
8x2+%2B+kx+%2B+7+=+0
a+=+8
b+=+k
c+=+7
b%5E2+-+4ac+=+0
k%5E2+-+4%2A8%2A7+=+0
k%5E2+-+224+=+0
k%5E2+=+224
k+=+sqrt%28224%29
k+=+sqrt%2814%2A16%29
k+=+%2B4%2Asqrt%2814%29 answer
k+=+-4%2Asqrt%2814%29 answer