Answer:
It looks like you cut off part of the questions...
Step-by-step explanation:
I think you just have to add all of the totals up??
The answer to the above question can be explained as under -
We know that, the sum of angles of triangle is 180°.
So, vertex angle plus base angles are equal are equal to 180°.
Let the vertex angle be represented by "v" and base angles be represented by "b".
Thus, v + b + b = 180°
So, v + 2b = 180°
Next, the question says, the vertex angle is 20° less than the sum of base angles.
Thus, 2b - 20° = v
<u>Thus, we can conclude that the correct option is A) v + 2b = 180°, 2b - 20° = v</u>
Hello!
To find cosine, use the formula cos = adjacent / hypotenuse.
According to angle B, adjacent of angle B is side A, and the hypotenuse is side c because the hypotenuse is always opposite the right angle.
Therefore, the cosine of angle B is a/c.
Answer:
a
Step-by-step explanation: