Answer:
75°
Step-by-step explanation:
Recall: SOH CAH TOA
Reference angle = ? = θ
Side length opposite to reference angle = 27
Hypotenuse length = 28
Apply SOH, which is:

Substitute


(nearest degree)
This is a system of equations. We solve it by setting it up so that when we add the two equations together, one of the variables will cancel out. We can do this by multiplying the bottom equation by 3. This will make our system of equations equal:
3a + b + 225
-3a + 3b = 75
Now we add these two equations together, because the a terms will cancel out.
4b = 300.
We can find what b is by dividing both sides by 4.
b = 75
Next, we plug in b in one of the equations and solve for a. You can use either equation, but I will use the second.
75 - a = 25
Subtract 25 from both sides and add a to both sides:
a = 50
So, the first option is correct. A = 50 and b = 75.
Answer:
A and C
Step-by-step explanation:
The absolute value of a negative number is positive; I don't know why A and C are identical though
If you have a unit circle, it means that you have a circle of radius r = 1 unit. So if we consider the scalene triangle of the figure, its vertical side is the sine of the theta angle and its horizontal side is the cosine of the theta angle. Then to find the hypotenuse of the triangle you use the Pythagorean theorem, thus relating the sine and cosine measures. I attach the solution.