The best way to find x is knowing the different angles and their properties and theorems.
A quadratic function whose vertex is the same as the y-intercept has the equation
y=x^2+k (where k is the y-intercept, with vertex (0,k))
Since the vertex coincides with the y-intercept, the axis of symmetry is x=0.
27 is 6
29 is 70
31 is 60
those are all of the answers.
