Question

y=x+2
x=y-2
yes its a function

Answer 1

@jim_thompson5910

Answer 2

You are correct. y = x+2 is a function and so is its inverse y = x-2 (since the original passes the horizontal line test)

Answer 3

y=-x^2-3 = y=plus&minus sqr -y-3 and no its not a functon