SOLUTION: How can I write x2-4x-5 in the form y=a(x-p)2+q

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Question 1083396: How can I write x2-4x-5 in the form y=a(x-p)2+q
Found 2 solutions by Boreal, MathLover1:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The vertex x value is at -b/2a=-(-4)/2=2; when x=2, y=4-8-5=-9. Therefore in vertex form it is (x-2)^2-9, taking the opposite sign for x and the value for y.
Check this
x^2-4x+4-9=x^2-4x-5.
The purpose of vertex form is to allow one immediately to see the vertex coordinates.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

y=x%5E2-4x-5 in the form y=a%28x-p%29%5E2%2Bq
first complete square:
y=%28x%5E2-4x%2Bb%5E2%29-b%5E2-5
y=%28x%5E2-4x%2B2%5E2%29-2%5E2-5
y=%28x-2%29%5E2-4-5
y=%28x-2%29%5E2-9 -> where a=1, p=2, and q=-9