Answer:
Last Option
Step-by-step explanation:
We have a triangle and we know its three sides.
We want to find one of your anguos. Then we use the cosine theorem.

Where

Now we solve for x from the equation

Answer:
Step-by-step explanation:
The angles labeled 4y - 8 and 79 + y are called vertical angles, and definition, vertical angles are congruent. That means algebraically, that
4y - 8 = 79 + y and
3y = 87 and
y = 29
Answer:
6
Step-by-step explanation:
Since the degree of the angle is 45, we know that the triangle is isosceles. That means that the sides of the triangle, not including the hypotenuse, has a length of 3√2.
Using the Pythagorean theorem, which is a^2 + b^2 = c^2, we have (3√2)^2 + (3√2)^2 = c^2.
Note: c is the hypotenuse of the triangle.
18 + 18 = c^2
= 36 = c^2
Therefore, c = 6.