Biking at 10 mph, it takes kristen an 1/2 hour to reach the train station to go to work. kristen then takes the train to work, and it takes another 1/2 hour for her to get to work when the train travels 20 mph. how far does kristen travel to work?

answer:  

step-by-step explanation:

here x represents the height of the pole,

and, the height of the shadow of the pole is 12 feet.

also, the angle of elevation from the top of the pole is 40°,

therefore,

by the low of sine,

which is the required equation for finding the value of x,