SOLUTION: Find p such that px^2-12x+4=0 has only one solution.

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Question 1029915: Find p such that px^2-12x+4=0 has only one solution.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
For there to be just 1 solution, the part
of the quadratic formula called the
discriminant must equal zero.
The discriminant is:
+b%5E2+-+4%2Aa%2Ac+
The quadratic formula is:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
when you are given the general form:
+f%28x%29+=+a%2Ax%5E2+%2B+b%2Ax+%2B+c+
this is how you find a, b, and c
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So, for 1 solution:
+b%5E2+-+4%2Aa%2Ac+=+0+
+b%5E2+=+4%2Aa%2Ac+
------------------
You are given:
+p%2Ax%5E2+-+12x+%2B+4+=+0+
+b%5E2+=+%28-12%29%5E2%0D%0A%7B%7B%7B+b%5E2+=+144+
and
+4%2Aa%2Ac+=+4%2Ap%2A4+
and
+144+=+4%2Ap%2A4+
+p+=+9+
If +p+=+9+, there is only 1 solution
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check the answer
+9x%5E2++-+12x+%2B+4+=+0+
+x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+
+x+=+%28+-%28-12%29+%2B-+sqrt%28+%28-12%29%5E2+-+4%2A9%2A4+%29%29+%2F+%282%2A9%29+
+x+=+%28+12+%2B-+sqrt%28+144+-+144+%29%29+%2F+18+
+x+=+%28+12+%2B-+0+%29+%2F+18+
+x+=+2%2F3+
So, there is only 1 solution