If sin (2x+7) = cos (4x-7), what is the value of x

Answer: 15

Step-by-step explanation:

Recall : if sin α = cos β, then α + β are complementary, that is

α + β = 90

Since sin (2x+7) = cos (4x-7), then (2x+7) and (4x-7) are complementary, that is:

2x + 7 + 4x - 7 = 90

6x = 90

x = 90/6

x = 15