SOLUTION: Find the vertex f(x)=x^2-4x-32

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Question 487732: Find the vertex
f(x)=x^2-4x-32
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
When the equation is in the form+f%28x%29+=+ax%5E2+%2B+bx+%2B+c+,
the x coordinate of the vertex is at +-b%2F%282a%29+
+f%28x%29=x%5E2-4x-32+
+a+=+1+
+b+=+-4+
+-b%2F%282a%29+=+-%28-4%29%2F%282%2A1%29+
+-b%2F%282a%29+=+2+
Now find +f%28x%29+, which is th same as y
+f%28x%29=x%5E2-4x-32+
+y+=+2%5E2+-+4%2A2+-+32+
+y+=+4+-+8+-+32+
+y+=+-36+
The vertex is at (2,-36)
Here's a plot:
+graph%28+400%2C+400%2C+-5%2C+10%2C+-40%2C+5%2C+x%5E2+-+4x+-+32%29+