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1. Hi! Could someone take a look at these two questions for me, please?

They're both from OCR Additional Maths June 2007.

Q13iii. I worked out the height as 36.3cm using the sine rule but in the mark scheme the height is actually 34.8cm. I'm wondering why I can't use the sine rule to get the same answer? (other than the fact that it's wrong)

Q14ii: I've done parts 1 and 3 but I don't really understand how to do part 2.
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2. (Original post by karmacrunch)
Hi! Could someone take a look at these two questions for me, please?

They're both from OCR Additional Maths June 2007.

Q13iii. I worked out the height as 36.3cm using the sine rule but in the mark scheme the height is actually 34.8cm. I'm wondering why I can't use the sine rule to get the same answer? (other than the fact that it's wrong)

Q14ii: I've done parts 1 and 3 but I don't really understand how to do part 2.
Wih Q14ii you're expected to solve the simultaneous equations.

It could look like this:

Which you then solve.
3. In Q13(iii), sine rule does work:

a/sinA = b/sinB

40/sin90 = h/sin60.5

Hence h = 40(sin60.5)/sin90 = 34.814... according to my calculator.
4. (Original post by TheOtherSide.)
Wih Q14ii you're expected to solve the simultaneous equations.

It could look like this:

Which you then solve.
Is that because you can rearrange the equations so Position A is 4=... and Position B is 4=...?

If so, I get it. Thank you!

(Original post by OscarTG)
In Q13(iii), sine rule does work:

a/sinA = b/sinB

40/sin90 = h/sin60.5

Hence h = 40(sin60.5)/sin90 = 34.814... according to my calculator.
I tried it again and my calculator's giving the same answer now. I must have typed it in wrong... repeatedly. Thank you though!
5. (Original post by karmacrunch)
Is that because you can rearrange the equations so Position A is 4=... and Position B is 4=...?

If so, I get it. Thank you!

Yep. And no problem!

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