The answer is (1,-4)
Remember that the vertex is the center of the parabola.
Ok so in order to find the answer to this problem we are going to Multiply

and

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what's the question your tryna figure out
Just keeping going with 16×-2=?×-2=?×-2 untill u get you your ninth nuber as well with tge 2 is a negative, so a a positive × a negative equal a negative and a negative × a negative equal
36÷6 is 6 to show your work for it maybe draw it out and better show the equation like when you solve a bigger problem.