Answer: 4
36.87 degrees
Step-by-step explanation:
The figure shown is a right angled triangle. It has three sides, one of which is the longest. The longest side is called the hypotenuse. Either of the shorter sides is called the opposite and the adjacent side(always the side carrying both the 90 degrees angle and the given angle).
Since the triangle is a right angled triangle,
We can apply Pythagoras theorem to get the opposite side.
Hypothenuse ^2 = opposite ^2 + adjacent ^2
5^2 = 4 ^2 + opposite ^2
opposite = √ 25 - 16
opposite = √9 = 3
Let the angle be # degrees,
Cos # = adjacent / hypothenuse
= 4/5 = 0.8
# = cos^-1 (0.8) = 36.87 degrees
