### Home > CALC > Chapter 7 > Lesson 7.1.2 > Problem7-21

7-21.

Patrick, who is $6$ feet tall, is walking way from a $10$-foot tall lamppost. If he casts a shadow that is $12.5$ ft long, how far from the lamppost is he?

Do you see two similar overlapping triangles? Recall that similar triangles have proportional sides. Set up a proportion and solve for $x$.