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1. Uhm maybe a stupid question...

Can you use the formula for an area of a non right-angled triangle using radians...

a= 1/2bh x sin theta

I have noticed I keep getting the same answer for area of triangle and area of sector the triangle is in. Which obviously is not correct - the formula are more or less the same.
2. (Original post by christinajane)
Uhm maybe a stupid question...

Can you use the formula for an area of a non right-angled triangle using radians...

a= 1/2bh x sin theta

I have noticed I keep getting the same answer for area of triangle and area of sector the triangle is in. Which obviously is not correct - the formula are more or less the same.
C can be in degrees or radians, just make sure your calculator is in the right setting

so an isoceles triangle with a small angle between the two equal length sides will give roughly the same answer in both formula, although the answers are not usually similar

Edit: could you post an example of a question and your working out

3. (Original post by christinajane)
Uhm maybe a stupid question...

Can you use the formula for an area of a non right-angled triangle using radians...

a= 1/2bh x sin theta

I have noticed I keep getting the same answer for area of triangle and area of sector the triangle is in. Which obviously is not correct - the formula are more or less the same.
Do you mean this?

If so, it should work for any triangle. Could you give me an example of your calculation?
4. https://0e90d90be05fe2865012661b731d...apter%2006.pdf

Question three in the mixed exercise - page 46 in the above link.

I may just be reading the question wrong!

The arc formed by a2 is part of the sector?

So area of sector is

A=1/2x17^2 x 2.16
a=120cm

So i worked out the area re of the triangle using the enclosed angle in radians using the formula:

A = 1/2 d x c x sine theta
a= 1/2 17 X 17 X sin 2.16
a = 120

I got the other parts to the question correct so the value for theta is correct.

I got the correct answer in the end using the formula for the segment.

So its more just for information/interest purposes!

I might just be reading the question wrong though....
5. (Original post by christinajane)

A=1/2x17^2 x 2.16
a=120cm
Silly calculation error.

Try doing that again,
6. Argh again!? haha

I think I am dyslexic....no joke!

Thank you Zacken.
7. (Original post by christinajane)
Argh again!? haha

I think I am dyslexic....no joke!

Thank you Zacken.
Not a problem! By the way, when you're replying to someone on here, you should press the "reply" button on their post so that the person receives a notification that you've replied to them!
8. Like this?

Thank you.
9. (Original post by christinajane)
Like this?

Thank you.
Not quite, it seems you haven't pressed the reply button under my post.

Not a problem at all!
10. Hahah oh god.

Like this then?

Was pressing the one to the right of your post....Is there any hope for me!?

Have a good day.

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