There is an intuitive definition of perpendicularity. It does not involve angle. Instead, it involves the notion of distance. Consider a point P and a line L not passing through it. If you wish to walk from P to L, the path of shortest distance is the **perpendicular drawn from P to L. **

This idea is used in the following problem, (similar to a problem from AMC – American Mathematical Contest 10 A, 2018).

# Part 1

# Part 2

Sir ,is an another way of solution of this problem(AMC 10A,2018).I send you my solution through Skype.