Find the vertex of the graph of the equation y = -2x^2 + 8x + 15 - 3x^2 + 7x - 25
Simplify as
y = -5x^2 + 15x - 10
x coordinate of the vertex = (-15) / (2 * -5) = 3/2
y coordinate of the vertex =
-5(3/2)^2 + 15(3/2) - 10 =
-45/4 + 45/2 - 10 =
45/4 -10 =
5/4
Vertex = ( 3/2, 5/4) = ( 1.5 1.25)
+1475 
