Question

In ΔFGH, f = 960 inches, g = 380 inches and h=820 inches. Find the measure of ∠F to the nearest degree.

Answer 1

Answer:

$m\angle F\approx 100^{\circ}$

Step-by-step explanation:

For any triangle, the Law of Cosines is given by $c^2=a^2+b^2-2ab\cos C$, where all three variables are interchangeable.

Therefore, we have:

$f^2=g^2+h^2-2gh\cos F,\\960^2=380^2+820^2-2(380)(820)\cos F,\\\cos F=-\frac{131}{779},\\F=\arccos(-\frac{131}{779})\approx \boxed{100^{\circ}}$