Math Is Fun Forum

JunPark

Member

Registered: 2020-06-30

Posts: 4

geometry

Hello I need help if my answers are on the right track.
I have 6 questions in total but I would appreciate if you can check my answers to my work.

1. Find the area of a regular hexagon with 8 feet sides.  Round the answers to the nearest whole number.
    - Show your work using the triangle method.
CA = 360 / 6 = 60
2sa + 60 = 180
2sa = 120
sa = 60
8 * (1/2) * root 3 = 4 * root3
(1/2) * 8 * (4 * root3) = 16 * root3
6 * 16 * root3 = 96 * root3
166.277 sq ft.
round = 166 sqft

    Part 2: Find the area of the same hexagon using two trapezoids.  Confirm that the answers to Part 1 and Part 2 are equivalent.
( 1 / 2 ) times 4 root 3 ( 8 +  16 ) = 48 root 3 = 83
83 times 2 = 166
A = 166 ft ^2

    Part 3:  Construct a prism from the above regular hexagon.  The height of the hexagonal prism is 5 feet. Find the surface area and the volume of this prism.
5 times 168 = 840
V = 840 ft ^ 3
8 times 5 = 40
40 times 6 = 240
168 times 2 + 240 = 576
Sa = 576 sqft ^2

Bob

Administrator

Registered: 2010-06-20

Posts: 10,640

Re: geometry

hi JunPark

Welcome to the forum.

First two parts look good to me.

Then this:

168 times 2 + 240 = 576

That should be 166 not 168.  I would suggest you go back to the un-rounded value, then x2, then round off again, to preserve maximum accuracy.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob