On the top problem: Angle A and Angle B are a right angle so it equals 90 degrees. If Angle B is 50 degrees that makes Angle A 40 degrees. Angle A and Angle C is a straight line and equals 180 degrees so if Angle A equals 40 degrees that means Angle C equals 140 degrees.
Answer: 
Step-by-step explanation:
We need to apply the following identity:
Then, applying this, you know that for 
:
We need to remember that:
and 
Therefore, we need to substitute these values into .
Then, you get:
The <u>second image</u> in the diagram is a hyperbola. As can be seen, the plane cutting the cone can be at any angle but never equal to the slant angle of the cone. This has a very important implication. The plane cuts both cones of the double-napped cone. The third double-napped cone of Figure 3 shows two hyperbolas.
Wait what is what which number goes to what letter
