Posted by lindsay on Thursday, May 3, 2012 at 10:27pm.
In the triangle ABC, the sides AB and BC have lengths 7cm and 8cm respectively, and angle B is obtuse. the area of the triangle is 14 root 3 cm^2. Find
a.The size of angle B
b. The length of AC

trigonometry  Reiny, Friday, May 4, 2012 at 12:08am
formula for area of triangle
= (1/2)ab sinØ, where Ø is the contained angle of sides a and b
(1/2)(7)(8) sinØ = 14√3
sin Ø = 28√3/56 = √3/2
Ø = 60°

trigonometry  Reiny, Friday, May 4, 2012 at 12:08am
now use the cosine law to find AC

trigonometry  shawulu, Sunday, March 6, 2016 at 6:13am
given triangle ABC with
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