Problema Solution
A post is casting a shadow on the ground. If the post is 3 ft taller than the shadow on the ground, and the tip of the shadow is 15ft from the top of the post, how tall is the post?
Answer provided by our tutors
let
x = the length of the shadow, x>=0
x + 3 = the height of the post
make a drawing and notice the right triangle with legs x and x+3 and hypotenuse 15 ft
using the Pythagorean Theorem we can write:
x^2 + (x + 3)^2 = 15^2
by solving we find:
x = 9 ft
click here to see the step by step solution of the quadratic equation:
x + 3 = 9 + 3 = 12 ft
the post is 12 ft tall.