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Help finding the missing side lengths for RQ and QP

Help finding the missing side lengths for RQ and QP-example-1
User Snuggles
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1 Answer

15 votes
15 votes

We have the following triangle

We have the hypotenuse and all the angles so we can use the law of sines


(a)/(\sin(A))=(b)/(\sin(B))=(c)/(\sin(C))

In this case take us a = 4, b = QP andc = RQ

First, we solve QP


\begin{gathered} (4)/(\sin(90))=(b)/(\sin(30)) \\ b=(4)/(\sin(90))\cdot\sin (30) \\ b=2 \end{gathered}

Second. we solve RQ


\begin{gathered} (4)/(\sin(90))=(c)/(\sin(60)) \\ c=(4)/(\sin(90))\cdot\sin (60) \\ c=2\sqrt[]{3} \end{gathered}

These are the solutions

To check this we can take out the hypotenuse using the Pythagoras theorem and check that


\begin{gathered} H=\sqrt[]{(2)^2+(2\sqrt[]{3})^2} \\ H=\sqrt[]{4+(4\cdot3)} \\ H=\sqrt[]{4+12} \\ H=\sqrt[]{16} \\ H=4 \end{gathered}

This is correct

In conclusion, these answers are:


\begin{gathered} QP=2 \\ RQ=2\sqrt[]{3} \end{gathered}

Help finding the missing side lengths for RQ and QP-example-1
User Boaz Hoch
by
2.9k points