Answer:
SA ==736^2
Without unit = 736^2
Step-by-step explanation:
Start with base of a triangle face
Base = 12 Height = 8
1/2 x 12 x 8 = 48 cm^2 one side face surface area
48 x 2 = 96 cm^2 two side face surface area bold
----
Sides
10 x 20 = 200 cm^2 one side face surface area
200 x 2 = 400 cm^2 two side face surface area bold
-----
base 20 x 12 = 240 cm^2 single base. bold
Add up those values in bold = 240 + 400 + 96 =736 cm^2
