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purplemonkey
09-20-2005, 03:54 PM
So, I am sure that this will be an easy question for ya'll tonight, I havent had a math class in a million years and I am trying to complete some much needed extra credit work, but I have gotten a little frustrated.

The question is.... A triangle has a perimeter of 161 miles, each of the two smaller sides of the triangle are two-thirds the lenght of the longest side. Find the lenght of each side.....
So, heres what I know....
I know that the perimeter is the lenght of all the sides togeather....
a + b + c = p
I can tell that two sides are the same lenght here so lets say a =b
and those are 2/3 of the side c....so should my equation look like

(c-1/3) + (c-1/3) + c =161 ??
and if that is right how in the world do i solve that? can i say 3c-2/3 =161? i am sure that isnt right....i am really going a bit crazy.... my math book doesnt have a geometry chapter really, so i am lost.

stapel
09-20-2005, 04:24 PM
They aren't "c units long, less 1/3 of a unit"; they are "two-thirds of the length of c". "c - 1/3" says the former; "(2/3)c" says the latter.

You're on the right track. Now make the above correction, and see where that takes you.

Eliz.

TchrWill
09-20-2005, 04:27 PM
A triangle has a perimeter of 161 miles, each of the two smaller sides of the triangle are two-thirds the lenght of the longest side. Find the lenght of each side

If the longest side is x, then 2x/3 + 2x/3 + x = 161 or 7x/3 = 161.

I suspect you can take it from here.

purplemonkey
09-20-2005, 04:33 PM
i think my biggest weekness would be dealing with fractions....

Ok...

2/3c + 2/3c+c=161

2 1/3c=161

c=69 161-69=92 92/2=46

so the sides are 69, 46 and 46?

i might ask you for help with a uniform motion problem next... :-)
if i am rigth and didnt screw that up thanks a ton

stapel
09-20-2005, 04:35 PM
To check the answer to any "solving" problem, plug the solution back into the original problem. If it "works", the solution is probably valid.

Eliz.

Gene
09-20-2005, 04:43 PM
It is simpler to leave it as an improper fraction.
2/3c + 2/3c+c=161
(2 +2 +3)c/3=
7c/3 = 161
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Try it that way next time.