Need Maths Help +REP!

[Sharon]

http://img691.imageshack.us/img691/5664/triangle04.th.gif

EXAMPLE:
A=5
B=4
C=3

How are you even meant to calculate the area of that I don't get it :S
Could do with a reply by Sunday.. Got HW on it xD
AND BTW, That is not a question on my HW xD

[Meree.]

If your calculating the area you times each side by one another. EX " A x B x C = 5 x 4 x 3 Hope it helped! : )

[Soka]

If your calculating the area you times each side by one another. EX " A x B x C = 5 x 4 x 3 Hope it helped! : )

Not this.

Only thing I can think of is.. if the sides are 3,4,5 then there may be a pythagorean triple formed.. so it will be a right angled triangle.

You can use the formula Area = 1/2 * base * height, which you can apply yourself.

This might not be correct though, my brains a bit dead at the moment!

Or were you just using the numbers 3,4,5 as example?

[Jay.]

Area = 1/2 x B x H doesn't apply here as all the sides are different.

If I'm correct, Meree is correct. Multiply all the sides together.

[Cyndia]

I thought the 1/2 Base * Height always worked? You just need to drop a perpendicular from one point of the triangle to the other side and use that as the height, and use the base as the length of the side you dropped the line to.

[Jay.]

Oh I thought it only worked on right-angled traingles as the base and height is easier to spot.

[kk.]

Not this.

Only thing I can think of is.. if the sides are 3,4,5 then there may be a pythagorean triple formed.. so it will be a right angled triangle.

You can use the formula Area = 1/2 * base * height, which you can apply yourself.

This might not be correct though, my brains a bit dead at the moment!

Or were you just using the numbers 3,4,5 as example?

This is correct. I know you definitely don't multiply all the sides together lol

you can either find the line don to form two right angled triangles, or try the 3 4 5 triangle rule

[Black_Apalachi]

This is a blast from the past but AB looks like a right angle. Therefore the whole triangle is half of a rectangle. So just multiply the two sides of this rectangle as you would normally, but because it's only half of one, divide it by 2.

So; (5x4)/2 = 10

I hated maths and thought I was rubbish at it even though they kept me in the top set for ever, so I may be wrong.

[kk.]

This is a blast from the past but AB looks like a right angle. Therefore the whole triangle is half of a rectangle. So just multiply the two sides of this rectangle as you would normally, but because it's only half of one, divide it by 2.

So; (5x4)/2 = 10

I hated maths and thought I was rubbish at it even though they kept me in the top set for ever, so I may be wrong.

not possible since the apparent hypotenuse is shorter than the other two sides

[Black_Apalachi]

not possible since the apparent hypotenuse is shorter than the other two sides

Why not?

[kk.]

oh im not saying your methods wrong, it would work if A=3 B=4 and C=5 but the way that hes given it makes it not possible to use that method.

right angled triangles has to have the longest side opposite the right angle, otherwise its not right angled.

[Black_Apalachi]

Oh yeah, I see what you mean. Either it's really not to scale or the measurements are wrong :P.

[Soka]

Area = 1/2 x B x H doesn't apply here as all the sides are different.

If I'm correct, Meree is correct. Multiply all the sides together.

This is never the case when working out the area of any 2d shape, i think you and Meree are getting confused with the perimeter, where you add all sides of the shape.

1/2*B*H does not apply if it is not a right angled triangle, not if all sides are different.

Maybe the OP could post the whole wording of the question, with a better diagram.

[Black_Apalachi]

I'm gonna bet that my method is correct but the measurements are the wrong way round :P.

[Soka]

I'm gonna bet that my method is correct but the measurements are the wrong way round :P.

I agree, as its the method I posted aswell before you :P.

I just didn't want to post the answer, people should work for it.

[Black_Apalachi]

Oh OK lol sorry, I didn't understand any of the other methods that were posted so must have read yours wrong :P

[scottish]

don't you use herons formula as you know all sides of triangle?


http://upload.wikimedia.org/math/6/8/a/68a3ad9c82dc198e451b8bad4155ab7a.png

where s is the semiperimeter of the triangle:

http://upload.wikimedia.org/math/e/c/5/ec50234ccbbd096784304c4048bc55a7.png


s = a + b + c / 2
s = 5 + 4 + 3 / 2
s = 12 / 2
s = 6


A = √s(s-a)(s-b)(s-c)
A = √6(6-5)(6-4)(6-3)
A = √6(1)(2)(3)
A = √36
A = 6



or

A = √(a+b+c)(a+b-c)(b+c-a)(c+a-b)/16
A = √(5+4+3)(5+4-3)(4+3-5)(3+5-4)/16
A = √(12)(6)(2)(4)/16
A = √576/16
A = √36
A = 6





dno not done that stuff in like 4 years ;l


edit; is it a right angled triangle or not? :S

[kk.]

don't you use herons formula as you know all sides of triangle?


s = a + b + c / 2
s = 5 + 4 + 3 / 2
s = 12 / 2
s = 6


A = √s(s-a)(s-b)(s-c)
A = √6(6-5)(6-4)(6-3)
A = √6(1)(2)(3)
A = √36
A = 6



or

A = √(a+b+c)(a+b-c)(b+c-a)(c+a-b)/16
A = √(5+4+3)(5+4-3)(4+3-5)(3+5-4)/16
A = √(12)(6)(2)(4)/16
A = √576/16
A = √36
A = 6





dno not done that stuff in like 4 years ;l


edit; is it a right angled triangle or not? :S
i have never seen that before.. ever lol. and ive finished a level so i doubt its the level theyre after

[scottish]

ah k, would have been better posting the exact quest instead of making one up as evidently its failed due to incorrect figures and by looking at the image can't judge if its right angled or not

also i'm nto english so don't know whats covered :P

[kk.]

i thought u meant you wernt actually english, like u were french lol. shouldve guessed by the name :P

[scottish]

yeh, or location kinda gives it away :P

shazzy post the real questions and stuff or close enough to it instead of completely made up numbers :P

[Soka]

yeh, or location kinda gives it away :P

shazzy post the real questions and stuff or close enough to it instead of completely made up numbers :P

Heron's formula may be the way to go about it. But, Heron's formula does not work on some triangles (triangles with a small angle for example). Therefore the answer is either 6, or 10.

[Sharon]

Http://img693.imageshack.us/img693/6904/ldt1005i.th.jpg

This is an question to my homework: Not sure if the picture is clear enough..
A = 6M *Thats the ____ Bottom line)
B = 5M (Left STRAIGHT Side)
6 thing = ??? (Not given.) Right diagonal side
Thats really unclear, Sorry.
Area pls. and formular

[kk.]

1/2 x b x h.

so 1/2 x 6 x 5 = ...

[Cyndia]

Yeah, if its a right angle (which is known as true as it has the square mark in the corner meaning 90 degrees), then simply use the 1/2 x base length x height.

Simple enough :)

[galbabe]

http://img691.imageshack.us/img691/5664/triangle04.th.gif

EXAMPLE:
A=5
B=4
C=3

How are you even meant to calculate the area of that I don't get it :S
Could do with a reply by Sunday.. Got HW on it xD
AND BTW, That is not a question on my HW xD

i think it is Area = B X H divide by 2
so i think a and b is b+h as they are the shorter of the 2 sides so maybe
5x4 divide 2 = 10 i think

but for volume i think you would multiply all 3.

hope i helped or even made any sense

[galbabe]

Http://img693.imageshack.us/img693/6904/ldt1005i.th.jpg

This is an question to my homework: Not sure if the picture is clear enough..
A = 6M *Thats the ____ Bottom line)
B = 5M (Left STRAIGHT Side)
6 thing = ??? (Not given.) Right diagonal side
Thats really unclear, Sorry.
Area pls. and formular

Area= bxh divided by 2
so = 6x5 divided by 2
= calulate it ur self lol

hope i helped and i am pretty sure that is how you do it.

Edited by SuperNic. (Forum Moderator): Please don't multiple post within the 15 minute edit time, thanks.