<u>Corrected Question</u>
Given a triangle with two sides 4.1 cm and 6.7cm and an Included angle of . Use the Law of Cosines to determine the length of the third side of the triangle.
Answer:
(D) 4.1cm
Step-by-step explanation:
Given a triangle with two sides 4.1 cm and 6.7 cm and an included angle of .
Using Law of Cosines
The correct option is D.
Sine rule
a/Sin(A) = b/Sin(B) = c/Sin(C)
b
C / |
a / _| A
B c
We know that a = 70 degrees and A = 25 foot
So 70/Sin(25) = Something
We also know we want C, and that c = 90 degrees
So 70/Sin(25) = 90/Sin(C)
Then you have to rearrange the equations. Start with Multiply all by Sin(C)
So [Sin(C)][70/Sin(25)] = 90
Then divide everything by 70/Sin(25)
So Sin(C) = 90/[70/Sin(25)]
Now you want to isolate C, so Sin-1 everthing
So C = Sin-1{90/[70/Sin(25)]}
So C = 32.91309534
To the nearest tenth, 32.9ft
Hope that helps :)
Answer:
45
Step-by-step explanation:
cause its going up by little
Option B. 13π/6 and Option D. 5π/6
To get the reference angle π/6 for the given angles we will check each angle given in the options.
A. 8π/6
Since 8π/6 means 240° which lies in 3rd quadrant. Therefore reference angle of 240°= 240-180 = 60° or π/3
B. 13π/6
13π/6 means 390° which lies in first quadrant.
Therefore reference angle = 390-360 = 30° or π/6
C. 3π/6
Since 3π/6 means 90° therefore reference angle of 90° is the same as 90°.
Or the reference angle is = π/2
D. 5π/6
5π/6 means angle is 150° which lies in second quadrant therefore reference angle of 150° = 180-150 = 30° or π/6
answer is Option B and D.