document.write( "Question 1209520: (39) Square SQUR has sides of length x. If triangle SQE is equilateral, find the area of triangle QAU.
\n" ); document.write( "Link to diagram: https://ibb.co/C58rZ09R
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Algebra.Com's Answer #851844 by greenestamps(13200)\"\" \"About 
You can put this solution on YOUR website!


\n" ); document.write( "Tutor @ikleyn has provided a response showing a valid solution using equations of the lines in the figure.

\n" ); document.write( "Here is a very different solution.

\n" ); document.write( "Draw segment AP parallel to SQ with P on QU. Let a be the length of AP.

\n" ); document.write( "Angle PUA is 45 degrees, so triangle APU is a 45-45-90 right triangle. The length of PU is then a.

\n" ); document.write( "Angle SQA is 60 degrees, so angle AQP is 30 degrees; that make triangle APQ a 30-60-90 right triangle. So then the length of QP is a*sqrt(3).

\n" ); document.write( "Use the lengths of PU and QP to find an expression for a in terms of the side length of the square.

\n" ); document.write( "\"a%2Ba%2Asqrt%283%29=x\"
\n" ); document.write( "\"a%281%2Bsqrt%283%29%29=x\"
\n" ); document.write( "\"a=x%2F%281%2Bsqrt%283%29%29\"
\n" ); document.write( "\"a=%28x%28sqrt%283%29-1%29%29%2F%28%28sqrt%283%29%2B1%29%28sqrt%283%29-1%29%29\"
\n" ); document.write( "\"a=%28x%2F2%29%28sqrt%283%29-1%29\"

\n" ); document.write( "Use the standard formula one-half base times height to find the area of triangle QAU. The base is x and the height is a.

\n" ); document.write( "\"A=%281%2F2%29%28x%29%28%28x%2F2%29%28sqrt%283%29-1%29%29=%28x%5E2%2F4%29%28sqrt%283%29-1%29\"

\n" ); document.write( "ANSWER: \"%28x%5E2%2F4%29%28sqrt%283%29-1%29\"

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