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kenewbie
Aug28-08, 04:20 PM
In a 3-4-5 triangle, how long is a line extending from the 90 degree angle down to the middle of the hypothenus.

Thats all I've been given. I think I am supposed to figure this out without trig, just basic geometric properties. But I'm stumped.

I can see that the hypothenus is divided into two 2.5 halves, but I cant seem to make any right angle triangles where I know two lengths.

k

dirk_mec1
Aug28-08, 04:35 PM
Use the cosine rule.

kenewbie
Aug28-08, 04:39 PM
Use the cosine rule.

I wanted a solution without trig.

But I just figured it out. A 90 degree angle has to be located on a circle with diameter equal to the hypothenus, and so the line must be equal to the radius of the circle, and so it is 2.5

k

dirk_mec1
Aug28-08, 04:46 PM
I wanted a solution without trig.

But I just figured it out. A 90 degree angle has to be located on a circle with diameter equal to the hypothenus, and so the line must be equal to the radius of the circle, and so it is 2.5

k
Your answer is correct.

Diffy
Aug29-08, 10:58 AM
You could have also just used Pythagorean theorem and a system of equations with 2 variables to work it out.

Diffy
Aug29-08, 12:28 PM
Never mind my last post. I read the problem incorrectly. I thought the line was perpendicular to the hypotenuse, not at its midpoint.