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The diagram shows part of a crane.

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Angle $x=\\var{x}^\\circ$, angle $y=\\var{y}^\\circ$ and length $AB=\\var{AB}$ m.

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Find the length of the inclined jib $BC$.

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Since we have two angles and one side, we should be able to use the sine rule. In this case

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\\[\\frac{a}{sin(A)}=\\frac{c}{sin~(C)}\\]

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We don't need to worry about the \"$B$\" section as we don't need it as length $b$ is not required.

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However, to get a matching \"Angle & Side Pair\" we need Angle $C$

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\\[C=180-(\\var{x}+\\var{y})=\\var{z}\\]

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Now, substituting our values into the Sine Rule we have:

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\\[\\frac{BC}{sin(\\var{x})}=\\frac{\\var{AB}}{sin(\\var{z})}\\]

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Rearranging:

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\\[ BC= \\frac{\\var{AB} \\times sin(\\var{x})}{sin(\\var{z})}=\\var{BC}\\]

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The Jib length $AB$ (in metres) is:

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