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Thread ID: 65502	2006-01-20 06:24:00	length of side ofa triange	wotz (335)	PC World Chat

Post ID	Timestamp	Content	User
422808	2006-01-20 06:24:00	OK this is for all those NCEA students who did maths, and anyone who remembers. I have a right angle triangle. Vertical side is 1m long. At right angle from bottom, another side goes out until a 70 degree angle will make the 3rd side meet the top of the 1st. How long is the bottom side? I need the answer for my weekend project of installing a sun shade.	wotz (335)
422809	2006-01-20 07:12:00	see wikipedia trig (en.wikipedia.org) . As I understand your problem, see the diagram at wikipedia. Angle A must be 20 degrees (and so Angle B is 70 degrees). length b is 1m length a is the unknown one tan (Angle A) = a / b so... tan(20) = a /1 length a must equal 0.36397 m I could be wrong though .. it is Friday.	gibler (49)
422810	2006-01-20 07:13:00	SOH CAH TOA	bob_doe_nz (92)
422811	2006-01-20 07:14:00	OK this is for all those NCEA students who did maths, and anyone who remembers. I have a right angle triangle. Vertical side is 1m long. At right angle from bottom, another side goes out until a 70 degree angle will make the 3rd side meet the top of the 1st. How long is the bottom side? I need the answer for my weekend project of installing a sun shade. Go buy a protractor then try a scale drawing. This is only 1 meter in height is it not? As I read this it will be a 70% from the bottom of the triangle toward the vertical line? This will give you if true a 20% angle from the top down I think. 1 tenth of a meter is 10cm and therefore your scale drawing will fit on a A4 page. You need to know how long the line at the bottom will be?	Elephant (599)
422812	2006-01-20 07:33:00	length a must equal 0.36397 m I could be wrong though .. it is Friday. No, thats right. Using the SOH CAH TOA method proves it correct.	bob_doe_nz (92)
422813	2006-01-20 07:51:00	see wikipedia trig (en.wikipedia.org) . As I understand your problem, see the diagram at wikipedia. Angle A must be 20 degrees (and so Angle B is 70 degrees). length b is 1m length a is the unknown one tan (Angle A) = a / b so... tan(20) = a /1 length a must equal 0.36397 m I could be wrong though .. it is Friday. You may be wrong. It appears to me that the length of b is the unknown here. You appear to be using capital letters for angles Care to recalculate or am I wrong? Or have I misunderstood? It seems to me that length a = 1 metre. Angle A = 70% therefore Angle B will = 20% There are only three knowns here. 1. Right angle triangle. 2. 1 metre vertical. 3. from bottom to top which two lines meet at Angle B.	Elephant (599)
422814	2006-01-20 08:13:00	Elephant ... The sum of the angles of an internal Right angle triangle ALWAYS equal up to 180 degrees	bob_doe_nz (92)
422815	2006-01-20 08:28:00	Elephant ... The sum of the angles of an internal Right angle triangle ALWAYS equal up to 180 degrees So what is your problem. My post says rightangle triangle which obviously points to one angle being exactly 90%. The only two other angles I mentioned were 70% and 20%. Now if we add 90% inferred as we are talking about a rightangle then add 70% from the original post then add my posted 20% I believe we get !80% which I thought I knew already. 90+70+20=180 I thought anyway. I don't need sines, cosines and tangents to figure that one out. I was not moaning about the maths used to calculate I just said that the unknown wanted here was length of the bottom of the triangle rather than the vertical side which was given as 1 metre.	Elephant (599)
422816	2006-01-20 08:41:00	To add to this the vertical side is length a or the distance between C and B as posted on this link. en.wikipedia.org Have a look and I think wotz wanted length "b" rather than length "a" which was given anyway.	Elephant (599)
422817	2006-01-20 09:05:00	To add to this the vertical side is length a or the distance between C and B as posted on this link. en.wikipedia.org Have a look and I think wotz wanted length "b" rather than length "a" which was given anyway. Yeah well I'm not 100% sure which angle he was meaning to be 70 degrees. I had length b as the vertical (just to confuse you i.e. triangle on its side). So assuming Angle A is 70 degrees .. you will get the same answer of 0.363 m.	gibler (49)
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