Find the surface area of the figures. (see attachment.)

Question

anonymous · Answer

attachment

callisto · Answer

For the upper figure
Area of each triangle = 5x9/2
Area of 4 triangles = 4(5x9/2) = 2(5x9) = 90
Area of the rectangles = 4 (12x9) = 432
Area of the square base = 9x9 =81
Total surface area = 90+432+81 = can you work it out?

anonymous · Answer

Yes, thank you!

callisto · Answer

For the bottom one
surface area of the hemi-sphere = (4 pi r^2) /2 = 2(5^2) pi = 50 pi
surface of area of the cylinder part = (2 pi rh) + (pi r^2) = 2 pi (5)(9) + pi (5^2) = 115 pi
Total surface area = 50 pi + 115pi = Can you work it out?

anonymous · Answer

Wow, you've explained this very clearly. Thank you so much. I couldn't figure out the second step for both problems. Thanks, again.

callisto · Answer

Welcome, so do you understand now?

anonymous · Answer

Yes! :)

callisto · Answer

Glad to hear :)