To get the vertex of the parabola we proceed as follows; y=-7(x-4)^2-5 The above can be written as: y=-7x^2+56x-117 The values of a,b and c are: a=-7, b=56 and c=-117 x=-b/(2a) x=-56/(-7*2)=4 but; y=-7x^2+56x-117 y=-7(4)^2+56(4)-117 y=-5 Thus; x=4 and y=-5 The vertex will be at point (4,-5)