a. Draw the graphs of y=4cosx and y=2x-x on the same set of axes for -2π<=x<=2π

(done)
b. Explain why all these solutions of the equation 4cosx=2-x must lie between x=-2 and x=6
I've drawn the solutions but not sure how to answer the question. Thx for your help

(b) why do you have 2-x must lie in [-4,4]