Answer:
x = 15
Step-by-step explanation:
[tex]cosx = sin(\frac{\pi}{2} - x)[/tex]
[tex]sin x = sin y = > x = sin^{-1}(sin y) = y => x = y[/tex]
[tex]sin(2x + 7)^{\circ} = cos(4x - 7)^{\circ}\\\\sin(2x + 7)^{\circ} = sin(\frac{\pi}{2} - (4x - 7))\\\\(2x + 7) = (\frac{\pi}{2}- (4x -7))\\\\2x + 7 = \frac{\pi}{2} - 4x + 7\\\\6x = \frac{\pi}{2}\\\\x = \frac{\pi}{12}[/tex]
x = 15