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mathboy15
Jul 17, 2008, 02:32 PM
Hi! =)
I have tried to solve this question for a long time now, but I'm still not able to solve it =S
Can you guys pllease help me? =)
THANKS =)

Mary and Jane were standing one behind the other, 2,3 m apart, each holding one of the two strings of a kite flying directly in front of them. The angles of elevation of the kite from the girls were 65 degrees and 48 degrees respectively.

assuming the ends of both strings are held at the same height above the ground, calculate the length of each string.

galactus
Jul 17, 2008, 04:33 PM
I am interpreting your problem as I have drawn.

Angle C=115 degrees

Length a=2.3 m

Angle B = 48 degrees

Angle A=180-(115+48)=17 degrees.

Now, we have enough info to use the law of sines.

\frac{b}{sin(48)}=\frac{2.3}{sin(17)}

Solve for side b, then use the law to find side c.

Unknown008
Jul 18, 2008, 02:40 AM
Remember the sine rule:

\frac{a}{sinA} = \frac{b}{sinB} = \frac{c}{sinC}

or vice versa, that is,

\frac{sin A}{a} = \frac{sin B}{b} = \frac{sin C}{c}

and the cosine rule,

a^2 = b^2 + c^2 - 2(b)(c)cosA

mathboy15
Jul 19, 2008, 09:18 AM
Thank you very much for your help guys :D