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#1 2006-03-07 10:29:15

kaken
Guest

Triangle

Hi! I was wondering.. how would you go into solving the perimeter and the area of this triangle with the data given. Thank you

tri02.jpg

#2 2006-03-07 11:24:58

Dionysus
Member
Registered: 2006-03-06
Posts: 9

Re: Triangle

I'm assuming H is the height, making H perpendicular to BC.
Therefore triangle abh is a right triangle, so by using pythagorean theorem,

:
144-81=63
Square root that to get 3√7 for B
You can do the same thing for the triangle on the right. adding
:
9 + 81 = 90
Simplify root 90 to get 3√10 for D
This makes your total perimeter 12+3√10+3√7+3 = 15+3√10+3√7 or about 32.4241

To find the area just find the base B + C = 3√7 + 3 and multiply it by your height of 9, and dividing by 2. The answer comes out to be exactly:

+

or about 49.2176.

So to sum up, your appx area is 49.2176, and your apprx perimeter is 32.4241. If you need it exact, look above for the radicals. (All in feet)

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#3 2006-03-07 13:44:29

kaken
Guest

Re: Triangle

Dionysus wrote:

I'm assuming H is the height, making H perpendicular to BC.
Therefore triangle abh is a right triangle, so by using pythagorean theorem,

:
144-81=63
Square root that to get 3√7 for B
You can do the same thing for the triangle on the right. adding
:
9 + 81 = 90
Simplify root 90 to get 3√10 for D
This makes your total perimeter 12+3√10+3√7+3 = 15+3√10+3√7 or about 32.4241

To find the area just find the base B + C = 3√7 + 3 and multiply it by your height of 9, and dividing by 2. The answer comes out to be exactly:

+

or about 49.2176.

So to sum up, your appx area is 49.2176, and your apprx perimeter is 32.4241. If you need it exact, look above for the radicals. (All in feet)

Oh! I see what you mean.. Thanks!

#4 2006-03-07 18:48:03

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,908

Re: Triangle

Well done, Dionysus!
Very good!


IPBLE:  Increasing Performance By Lowering Expectations.

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#5 2006-03-08 01:05:56

Dionysus
Member
Registered: 2006-03-06
Posts: 9

Re: Triangle

Thank You smile

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