Question 622084
Plug in any x value you want. I'm going to plug in something close to 2 (since the x coordinate of the vertex is x = 2)


So I'll pick x = 3


Plug in x = 3


y=-x^2+4x-7 


y=-(3)^2+4(3)-7 


y = -9 + 4(3) - 7


y = -9 + 12 - 7


y = -4


So when x is x = 3, y is y = -4. 


So another point on the parabola is (3,-4)


By symmetry (along the axis of symmetry x = 2), another point is (1,-4). This is because x = 1 is exactly the same distance away from the axis of symmetry as x = 3 is. So these two x values produce the same y value.


You can plug in any amount of x values you want to generate any number of extra pairs of points.