9514 1404 393
Answer:
e = 25.7 m
Step-by-step explanation:
Put the given numbers in the given formula and do the arithmetic.
[tex]e^2=d^2+f^2-2df(\cos{E})\\\\e^2=11.9^2+18.5^2-2(11.9)(18.5)\cos{114^\circ}\approx 662.946\\\\e\approx\sqrt{662.946}\approx25.74774\\\\\boxed{e\approx25.7\text{ m}}[/tex]
