John measured the angle of elevation to the top of a tower as 50°. He walked 20 m towards the tower and measured the angle of elevation as 65°.

Calculate the height of the tower to the nearest centimetre.

Please explain the answer. One sec, I'll be clipping a diagram of what I got so far.

Question

John measured the angle of elevation to the top of a tower as 50°. He walked 20 m towards the tower and measured the angle of elevation as 65°.

Calculate the height of the tower to the nearest centimetre.

Please explain the answer. One sec, I'll be clipping a diagram of what I got so far.

anonymous · Answer

|dw:1402360771737:dw|

Please use sine rule.

anonymous · Answer

That's not the diagram provided, that's my workings out

tkhunny · Answer

Do you mean they may not APPEAR to be Right Angles?  If they are not Right Angles, why are you using the sine function?

|dw:1402373259660:dw|

anonymous · Answer

I don't know, I'm using the sine rule.

a/sinA = b/sinB = c/sinC

tkhunny · Answer

Why?  It seems a tangent would be more appropriate.

anonymous · Answer

The course I'm doing is about the sine rule. :/

tkhunny · Answer

|dw:1402373880871:dw|

Okay, where does that leave us?