Where is the vertex of the quadratic y = (x -7)2 + 9

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rule: common equation for a parabola is y=ax²+bx+c. If to re-write this equation in the form y=(x+m)²+n, then point (-m;n) is vertex of this parabola.
According to the described rule vertex is (7;9).
The graph of this function is in the attachment.