53b−7b−6b+1 if b=25 Please help me with this problem! And what is the simplified expression?
1 answer:
You might be interested in
9514 1404 393
Answer:
(a) 42.3°
Step-by-step explanation:
Side 'a' is the shortest of three unequal sides, so angle A will be the smallest angle in the triangle. Its measure can be found from the Law of Cosines.
a² = b² +c² -2bc·cos(A)
cos(A) = (b² +c² -a²)/(2bc) = (21² +25² -17²)/(2·21·25) = 777/1050
A = arccos(777/1050) ≈ 42.3°
The measure of angle A is about 42.3°.
_____
<u><em>Additional comment</em></u>
The smallest angle in a triangle can never be greater than 60°. This lets you eliminate choices that exceed that value.
