Question

Finding the Angle
Finding the Angle
@Mathematics

Answer 1

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Answer 2

in the diagram "a" is the angel that you need to find and "x" is the length of side BC.
you trigonometry to find "x" first:\[\sin 21.8=6/x\]\[x=6/\sin 21.8\]then, in triangle CBD angel BCD must be 90, so again use trigonometry:\[\tan a=13/x=13/\frac{6}{\sin21.8}=13*\frac{sin21.8}{6}=\frac{13\sin21.8}{6}\]\[a=\tan^-1(\frac{13\sin21.8}{6})\]use a calculator to work this out and you should have your answer.