trigonometry
posted by anonymous on .
The formula log(w) = 2.866 + 2.722log(h) estimates the "average" weight w in pounds of a girl h inches tall. To the nearest tenth of a pound, estimate the "average" weight of a girl who is 47 inches tall.

Do you have a calculator? I assume that the log you are talking about is base 10.
log(47) = 1.672
log(w) = 2.866 + (2.722)(1.672) = 1.6855
w = 10^1.6855 = 48.5 lb
This subject is not trigonometry. It is logarithms. You need a scientific/math hand calculator or a computer to do it. In my school days, we used log tables or a slide rule. 
What is Trigonometry?