Question

how to do this help? will become fan. EXPLAIN.

Answer 1

remember that we have two nice rules for a triangle
1) sine rule -> when we have an angle and side opposite to it - > easiest
2) cosine rule -> when we do not have any angles but all sides -> a wee bit longer

Answer 2

this this case, we have the angle B and the side opposite to it, we have the side "a" and need to find the opposite angle A
so, we use sine rule
\[{\sin A\over a}={\sin B\over b}\\
{\sin A\over23}={\sin(50^\circ)\over19}
\]

Answer 3

@electrokid I get 66.9?

Answer 4

@electrokid but thats not in my answers?:o

Answer 5

\[\sin A=23\times{0.766\over19}=0.927\\
A=\sin^{-1}(0.927)=?
\]

Answer 6

67.97

Answer 7

\(68^\circ\) is not an answer?

Answer 8

Alright I got it thank you. Could you help me with this one please?

Answer 9

so, what rule can we use here?

Answer 10

sine

Answer 11

did you follow the rules I put up in the first post?

Answer 12

Im so sorry I meant cosine!

Answer 13

k.
so set up the equation for cosine rule for angle R

Answer 14

equation : 8^2 = 4^ + 7^2 - 2(4)(7) cos R?

Answer 15

@electrokid

Answer 16

yes

Answer 17

Alright I got 89.02