ABC is a triangle

AB=8cm

BC=14cm

Angle ABC=106

Calculate the area... correct to 3 significant figures.

Even with splitting it up into right angled triangles doesn't work...

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- Jan 6th 2010, 12:24 PMMukilabWorking out area
ABC is a triangle

AB=8cm

BC=14cm

Angle ABC=106

Calculate the area... correct to 3 significant figures.

Even with splitting it up into right angled triangles doesn't work... - Jan 6th 2010, 12:30 PMpickslides
$\displaystyle A = \frac{1}{2}ac\sin(B)$

In your case

$\displaystyle A = \frac{1}{2}\times 14\times 8 \times \sin(106)$ - Jan 6th 2010, 12:47 PMMukilab
- Jan 6th 2010, 12:48 PMMukilab
This calculates to -40...... can't be the area.

- Jan 6th 2010, 12:58 PMpickslides
- Jan 6th 2010, 01:05 PMpickslides
- Jan 7th 2010, 07:39 AMMukilab
I do study, I just find it hard to locate the correct and adequate resources. I don't know any greek signs apart from theta so if you could explain that in words....

- Jan 7th 2010, 11:31 AMpickslides

The only greek letter in my statement was theta.

The statement means that for all angles between 0 and 180 sin will be positive. Therefore the result you are after must be positive as we are taking that postive result and multiplying it by only positive numbers. - Jan 7th 2010, 11:37 AMe^(i*pi)
- Jan 7th 2010, 12:21 PMMukilab
Pickleslides, what does the upside down A mean than?

- Jan 7th 2010, 12:24 PMpickslides
- Jan 7th 2010, 12:35 PMMukilab
Har so I was right ^^

Thanks - Jan 7th 2010, 01:08 PMDvdHntr
How can't you split into right angled triangles??

First use cosine rule to work out the length of the remaining side = 17.94cm

Then use sine rule and basic calculation (180-angle = other angle) to work out

BCA = 25.39

CAB = 48.61

Then use use trig functions (sine and cosine) to work out length and height of triangles

And calculate the triangle with 1/2 base times height.

A = 53.8cm2 - Jan 7th 2010, 01:11 PMpickslides