Question

The function LaTeX: L=.8T^2 L = .8 T 2 models the relationship between L, the length in feet of a pendulum, and T, the period in seconds of the pendulum. Which value is closest to the period in seconds for a pendulum that is 30 feet long?

Answer 1

6.1 seconds.

In the equation L=0.8T², we will substitute 30 for L:

30 = 0.8T²

Divide both sides by 0.8:
30/0.8 = 0.8T²/0.8
37.5 = T²

Take the square root of both sides:

√37.5 = √T²
6.1 = T