Point o is the center of the circle, what is the value of x?

The rows and columns of lattice points in a three-by-three square array are evenly spaced one unit apart. how many distinct triangles with at least one side of length 2 units can be drawn using three lattice points for the vertices?

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left

If wxyz is a square, which statements must be true?