Part of the road is to be on a parabolic curve given by a function of the form y = ax2 + bx + c where x and y are local co-ordinates.

Question

The road alignment must pass through the following 3 points:-

x = 150m y = 190.650m
x = 300m y = 611.450m
x = 450m y = 831.141m

5.1. Substitute each pair of x,y values to produce 3 simultaneous equations with unknowns a, b and c.
5.2. Solve these simultaneous equations to determine the values of a, b and c and substitute these into the standard form to give the particular function for the road curve.
5.3. Use this function to determine the y ordinates at x = 220m and the x ordinate at y =700m

Answer 1

surely you can at least do part 1. ?

Answer 2

Try to substitute your x and y