Solve x-y=3 x+2y=-6 using substitution

Given (1+cosx)/(sinx) + (sinx)/(1+cosx) =4, find a numerical value of one trigonometric function of x. a. tanx=2 b. sinx=2 c. tanx=1/2 d. sinx=1/2

If g(x) is an odd function, which function must be an even function?

What is the answer to this question? i'm a bit stumped. also how do i do it? 5(x - 4) = 2(x + 5)