Maths Help needed!!!!

[karenmac60]

Ok, my daughter has maths homework that she can't work out (cos she was in EuroDisney when they covered it in class) and I don't have a clue. She has to work out the height of a triangle, from part way along the base to the highest angle. She has the lengths of the 3 sides (all different) and the area, but neither of us has a clue what the formula is for working it out. Any maths whizzes out there that could guide us in the right direction?

Thanks

Karen

[mollykins]

If you split the triangle in half from the top point two the bottom, you get two right angled triangles. You might be able to use pyrathagorus to work it out (or is it more likely to be triganometry?)

[mollykins]

What are the length of the sides? any angles? if there are no angles given you should be able to use good old pythag, a^2+b^2=c^2 (but makes sure c, is the longest side, else you'll have to rearrange it slightly)

[karenmac60]

I think it'll be triganometry Molly, I have the total length of the base, but the measurement I need doesn't go to the midpoint so I then only have the hypotenuse of each of the triangles after splitting it. Thanks though :)

[scotman]

Karen

I seem to remember that this needs 'The Cosine Rule'(which I would have to look up or google) This will give the angles as well(I think). Once you know the lengths and angles the rest gets a lot simpler.

[karenmac60]

The sides are 15, 20 and 25 and the area is 150 if that is any help.

[AlBags]

Height = 2xArea/Base I believe.

[benny3008]

http://www.calcenstein.com/calc/1114_help.php hope this helps. :-)

[scotman]

This is what I meant

http://www.y-maths.co.uk/trisincosrl.htm

[sherrardk]

Has she got a friend in the same class who she could phone and ask for the formula?

[China Doll]

Would it not just be easier to let her get a detention for not doing her homework? It's probably character building..... ;0)

[sherrardk]

You have to be careful helping her as they seem to keep changing the way that kids are taught to do maths - the way my son has been taught to do 'big' multiplications is ridiculous but that's the way the school want it done.

[scotman]

AlBags is correct

[AlBags]

Scalene triangle I seem to remember from GCEA days.

[wolf63]

How many adults does it take to do maths homework = quite a few as most of us forgot it all after leaving school.

[bibblebub]

I posted this earlier http://www.theanswerb...e/Question981646.html - it will at least confirm your answers

[benny3008]

lol wolf 63, i left 2 years ago and i can't remember how to do it either! :-/

[Prudie]

Area of any triangle is:
A = 1/2 x base x height
If you move this round you get;
height = 2 x Area divided by base

You will get a different height depending which base you use but if you take 15 for example then:
height = 2 X 150 divided by 15 = 20

[AlBags]

What's this 'highest angle' lark?
And 'part way along the base'?

[DTCwordfan]

It is a bit liek the old story of "Why does it take take ten Californians to change a light bulb?"

"One to change it and nine to share the experience......."

[AlBags]

Thanks Prudie x
That confirms my original suspicions : )