Please solve the programming task below using a self-contained code snippet in a markdown code block.

You are given an array points containing the coordinates of points on a 2D plane, sorted by the x-values, where points[i] = [xi, yi] such that xi < xj for all 1 <= i < j <= points.length. You are also given an integer k.
Return the maximum value of the equation yi + yj + |xi - xj| where |xi - xj| <= k and 1 <= i < j <= points.length.
It is guaranteed that there exists at least one pair of points that satisfy the constraint |xi - xj| <= k.
 
Please complete the following python code precisely:
```python
class Solution:
    def findMaxValueOfEquation(self, points: List[List[int]], k: int) -> int:
```