Answer:
surface area =782
Explanation:
start with finding the area of all the rectangular faces and adding them together.
-face 1: 20*10=200
-face 2: 20*14.1=282
-face 3: 20*10=200
add them all together--200+282+200=682
next find the area of the two triangular bases
-base 1: 1/2bh=(1/2)(10)(10)=(1/2)(100)=50
-base 2: 1/2bh=(1/2)(10)(10)=(1/2)(100)=50
add those two areas together--50+50=100
finally, add the combined areas of the the rectangular faces and the two triagular bases together to get the total surface area of the triangular prism--
--100+682=782
that means 782 is the total surface area of the triangular prism.