Designing a Curve to Pass Through a Fixed Point

Given: r, VPI station and elevation, a point (P) elevation and station on the curve.
Required: Curve length
Solution:
- Substitute in the tangent offset formula, the only unknown is L: Y = YBVC + g1 X + (r/2) X2
- Remember that:
  - YBVC = YV - g1 (L/2), only L is unknown
  - X is distance from BVC in stations, it is not the given station of P, to compute it, add or subtract the distance V-P to/from L/2