document.write( "Question 541207: How do you find the area of a 30,60,90 triangle with a height of 4 inches and an unknown base?\r
\n" ); document.write( "\n" ); document.write( "P.S. the answer must be a radical number
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #354105 by oberobic(2304)\"\" \"About 
You can put this solution on YOUR website!
Area = 1/2 * Base * Height
\n" ); document.write( ".
\n" ); document.write( "Height = 4 (given)
\n" ); document.write( ".
\n" ); document.write( "The triangle is a 30-60-90. (given)
\n" ); document.write( ".
\n" ); document.write( "The 30-60-90 triangle is a special triangle that most students have to learn to manipulate.
\n" ); document.write( "The sides of the triangle have a well-known relationship.
\n" ); document.write( "The side opposite the 30 degree angle is the short side.
\n" ); document.write( "The side opposite the 90 degree angle is the hypotenuse. It is twice the length of the short side.
\n" ); document.write( "Applying the Pythagorean Theorem, we can calculate the third side. It will have a sqrt(3) component.
\n" ); document.write( ".
\n" ); document.write( "The relationships can be used to define the lengths of the sides.
\n" ); document.write( "Let's call the short side S for \"short\".
\n" ); document.write( "Call the hypotenuse H.
\n" ); document.write( "Call the third side L for \"long\" because it is longer than S. Of course, it is shorter than H.
\n" ); document.write( ".
\n" ); document.write( "\"+S+=+%281%2F2%29%2AH+\"
\n" ); document.write( ".
\n" ); document.write( "\"+L+=+%281%2F2%29%2AH%2Asqrt%283%29+\"
\n" ); document.write( ".
\n" ); document.write( "Therefore, we can determine:
\n" ); document.write( ".
\n" ); document.write( "\"+L+=+S+%2A+sqrt%283%29+\"
\n" ); document.write( ".
\n" ); document.write( "In what may be a typical layout, the L side is shown vertically, which makes it the height.
\n" ); document.write( ".
\n" ); document.write( "From the last equation (above), we can deduce that:
\n" ); document.write( ".
\n" ); document.write( "\"+S+=+L+%2F+sqrt%283%29+\"
\n" ); document.write( ".
\n" ); document.write( "That means:
\n" ); document.write( ".
\n" ); document.write( "\"+Area+=+%281%2F2%29+%2A+%28L%2Fsqrt%283%29%29+%2A+L+\"
\n" ); document.write( ".
\n" ); document.write( "\"+Area+=+%281%2F2%29+%2A+%284%2Fsqrt%283%29%29+%2A+4+\"
\n" ); document.write( ".
\n" ); document.write( "\"+Area+=+%281%2A4%2A4%29%2F%282%2Asqrt%283%29%29+\"
\n" ); document.write( ".
\n" ); document.write( "\"+Area+=+8%2Fsqrt%283%29+\"
\n" ); document.write( ".
\n" ); document.write( "Done.
\n" ); document.write( "
\n" );