SOLUTION: how many times does the graph of y=16x^-8x+1 intersect the x-axis?

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Question 617138: how many times does the graph of y=16x^-8x+1 intersect the x-axis?
Found 2 solutions by dragonwalker, jsmallt9:
Answer by dragonwalker(73) About Me  (Show Source):
You can put this solution on YOUR website!
May I ask if that IS a 1 in your equation or should it be 16?
Because I suspect that it crosses the x axis once at x = 4

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
y=16x%5E-8x%2B1
Places where a graph crosses the x axis are called x intercepts. Points on the x axis have a y coordinate of 0. So to find these points you set y = 0:
0=16x%5E-8x%2B1
Now we factor (or use the Quadratic Formula). This will factor according to the a%5E2+-2ab+%2B+b%5E2+=+%28a-b%29%5E2 pattern with the "a" being 4x and the "b" being a 1:
0+=+%284x-1%29%5E2
According to the Zero Product Property a product is zero only if a factor is zero. So:
4x - 1 = 0
Solving this we get:
x+=+1%2F4

So there is only one x intercept: (1/4, 0). And the answer to the question is: Once.