Plotting two or more curves using Plot and Functions app

[Anthony The Koala]

ISet up four functions using Apps -> Functions and then plotting them using Plot button.

Setting up the equation in Apps -> Functions
All are ticked:
F1(X) = X= -2
F2(X) = Y = 2
F3(X) = X^2
F4(X) = X^3

Press Plot:
result: F3 and F4 are plotted BUT not the vertical and horizontal lines of F1(X) amd F2(X) respectively.

Help as to why I don't have the vertical and horizontal lines plotted.

Thank you
Anthony, Sydney