Calculus help please!!!!!

Question

A lighthouse is stationed at a point P some distance away from the nearest point Q on a straight shoreline. It is found that the beam of light is moving alon the shore at a rate of 220pi m/s when it passes a point R on the shoreline 1km away from Q. How far away is the lighthouse from the shoreline?

Answer 1

Lighthouse sa shore ka perpandicular distance=a shore par moving light ka distance from point qQ= x angle b/w beam and perpandicular =@ tan @ = x/a sec sec d0/dt =1/a:dx/dt do /dt = 1/a dx /dtcos cos