trigonometry - modelling and problem solving

I can't visualise this problem at all!!

From a point due North of a tower, the angle of elevation to the top of the tower is 45 degrees. From point B, 100M ON A BEARING OF 120 DEGREES FROM a, THE angle of elevation is 26 degrees. Find the height of the tower.

Re: trigonometry - modelling and problem solving

Solution: Given h/a=tan 45°

a=h

h/b=tan26°

b=h/tan26°

b=2.05h

100²=a²+b²-2abcos 120°

10000=h²+(2.05)²-2*h*2.05*h

h=37.1m

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Re: trigonometry - modelling and problem solving

Quote:

Originally Posted by

**brosnan123** Solution: Given h/a=tan 45°

a=h

h/b=tan26°

b=h/tan26°

b=2.05h

100²=a²+b²-2abcos 120°

10000=h²+(2.05)²-2*h*2.05*h

h=37.1m

Attachment 28979