3 (4x + 6) = 21
4x + 6 = 21/3
4x + 6 = 7
4x = 7 - 6
4x = 1
x = 1/4



→ Substitute cos 2x and sin 2x by their expressions

→ Subtract both sides by sin x

→ Take sin x as a common factor in the right side

From the graph, the equation has 4 solutions, the intersection points between the 2 graphs
Answer:
Step-by-step explanation:
84/105 = 4/5