<em><u>The equation of the function is:</u></em>
<em><u>Solution:</u></em>
<em><u>The vertex form of equation is given as:</u></em>
Where, (h, k) is the vertex
Given that, The graph of a quadratic function has the vertex (4, 2)
(h, k) = (4, 2)
Substitute in eqn
And passes through the point (5,5)
Substitute (x, y) = (5, 5) in above
Substitute a = 3 and (h, k) = (4, 2) in vertex form
Thus the equation of function is found