94.8k views
4 votes
HELPPPP WITH MATH QUESTION

HELPPPP WITH MATH QUESTION-example-1
User Puritii
by
8.6k points

2 Answers

5 votes

Answer:I think its the third answer

User SMaZ
by
6.8k points
4 votes

ANSWER

The correct answer is B.

Step-by-step explanation

The cosine rule can be used to find the relation for b.

According to the cosine rule:


{b}^(2) = {a}^(2) + {c}^(2) - 2ac \cos( B )We have that a=4 and c=5 and B=60°

We plug in these values to get:


{b}^(2) = {4}^(2) + {5}^(2) - 2(4)(5) \cos( 60 \degree )


{b}^(2) = 16+ 25 - 40 ( (1)/(2) )


{b}^(2) = 16+ 25 - 20

Take positive square root.


b = √(25 + 16 - 20)

The correct answer is B

User Superdweebie
by
7.2k points