Try this option:
1. rule: cosα=sin(90°-α), it means that cos 3x=sin(90°-3x);
2. sin(90°-3x)=sin(x+18°); ⇔ 90°-3x=18°+x; ⇔ x=18°.
Answer: x=18°.
-85, -87, -89
Step-by-step explanation:
1. Divide -261 by 3. (Answer is -87)
2. Take the odd integer before it (-85) and the odd integer after it (-89).
Answer:
the B value is The Middle number, which is the number next to and multiplied by the x
