a = The cost of the pizza.
b = The cost of the pizza and sales tax.
f(a) = The cost of the pizza.
g(b) = The cost of the pizza and sales tax.
g(f(a)) = The cost of the pizza, sales tax, and delivery fee
Try this suggested option (all the details are in the attachment), the correct orientation is marked with red and green colours.
P.S. The point C has coordinates: (3;1). If to traslate it 6 units right and 5 units down, then (3+6;1-5) ⇒ (9;-4). The same principle is for the others points A, B and D. Note, after translation point A is point E, B⇒F, C⇒G and D⇒H.
A and C is 59 because 1 line is 180 degrees so you add 75 and 46 and you get 121 and then do 180 - 121 and you get 59