Find the surface area of the figure below. The triangle is an equilateral triangle.

Question

anonymous · Answer

attachment

directrix · Answer

The surface area can be thought of as the areas of the three rectangular lateral faces added to the area of the two equilateral triangles.

directrix · Answer

I think of it in terms of a formula:

Total Area = p*h + 2B where p is the perimeter of the Base, h is the height of the prism, and B is the area of a base, in this case, an equilateral triangle.

directrix · Answer

T.A. = p*h + 2B 
TA = (5*3)*20 + 2* ( 1/2 * 4.3 * 5)
TA = ?       @dopegyal_

directrix · Answer

@dopegyal_    A question awaits you.

anonymous · Answer

3246.5

anonymous · Answer

wait.

anonymous · Answer

5*3=15 * 20 = 300 ... 300+2=   302/2=151... 151*4.3*5 = 3246.5 !? Whhy do I keep getting this answser?

anonymous · Answer

I got 321.5 now... I did what was in parenthesis first.

directrix · Answer

300 is the sum of the areas of each of the 3 rectangular faces of dimension 20 by 5.

Then, there are two equilateral triangles.

A =2*  1/2 * 5 * 4.3 = 21.5 --> Base Areas

Total: 321.5

directrix · Answer

Okay, you self-diagnosed your error. Good.