HELP WITH ALTITUDE IN A TRIANGLE ?

Question

i need help doing triangle altitudes in math class (geometry) we have to find the altitude of a triangle with the 3 points how would i do this without graph paper

Answer 1

Do you mean find it like locate it or like measure it?

The Altitude is a line from one point to the opposite side such that it crosses the side at a right angle.  If you know the length of the three sides, you can calculate the length of the altitude.  Use the base (the side the altitude crosses) as x and length-x.  Do two calculations like Alt^2 = SideA^2 - x^2 and Alt^2 = SideB^2 - (Base-x)^2.  You should be able to find Alt (the length of the altitude).  

Answer 2

You should have posted this under math, not geography.   I'll say you need help.

Answer 3

If your question were placed in the mathematics section

not in the geography section you might get a better chance at getting an answer.

Answer 4

Determine the altitude of a triangle.

From: Doctor Pat

Subject: Re: Altitude of a triangle

You are given three sides of a triangle. You can use Heron's formula

to find the area. Once you know the area you know that for any base,

1/2 the base times the height is also the area.

Since the altitude to PQ is requested, let PQ be the base. The height

you find goes perpendicular to PQ up to vertex R. If you do not know

Heron's formula here it is:

Find the perimeter of the triangle and divide by two. This is called

the semi-perimeter, S. In your problem it is (11+25+30)/2 = 33.

Now you need to subtract each side one at a time from S (to be brief I

will use a, b, and c for the lengths of the three sides)

S - a = 33 - 30 = 3

S - b = 33 - 25 = 8

S - c = 33 - 11 = 22.

Now use these three numbers and S, multiply them all together, and

find the square root. This is the area.

  

Area = sqrt(S (S - a)(S - b)(S - c))  

Now since area = 1/2 B * h  plug in this value for the area, and 11

for the base, and solve for h, and you are done.  

→ Or use this calculator link below (just fill in the lengths of the three sides).

→ http://www.mste.uiuc.edu/dildine/heron/a...