document.write( "Question 155021: The perimeter of an isosceles triangular lot is 210 m. If each congruent side is 2/3 the third side, what are the lengths of the sides. Find the area of the triangle. \n" ); document.write( "

Algebra.Com's Answer #114421 by jojo14344(1513) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let known that $\"sideA=A\"$ & $\"sideB=B\"$ are congruent and the 3rd side= $\"sideC=C\"$
\n" ); document.write( "So,
\n" ); document.write( " $\"A=%282%2F3%29C\"$
\n" ); document.write( " $\"B=%282%2F3%29C\"$
\n" ); document.write( " $\"C=C\"$
\n" ); document.write( " $\"Perimeter=A%2BB%2BC\"$ , or since $\"A=B\"$ -- congruent, then $\"P=2A%2BC\"$
\n" ); document.write( " $\"210m=%282%2F3%29C%2B%282%2F3%29C%2BC\"$
\n" ); document.write( " $\"210=%284%2F3%29C%2BC\"$
\n" ); document.write( " $\"210=%284C%2B3C%29%2F3\"$
\n" ); document.write( " $\"630=7C\"$ ---> $\"cross%28630%2990%2Fcross%287%29=cross%287%29C%2Fcross%287%29\"$
\n" ); document.write( " $\"C=90meters\"$ ------------------------> side C
\n" ); document.write( " $\"A=B=%282%2F3%2990=180%2F3=60meters\"$ --------> side A & side B
\n" ); document.write( " $\"Area=%281%2F2%29bh\"$
\n" ); document.write( "Remember: $\"base=sideC\"$ = $\"90\"$
\n" ); document.write( "Solve $\"h\"$ by Pyth theorem:
\n" ); document.write( " $\"B%5E2=h%5E2%2B%28C%2F2%29%5E2\"$ -----. we use only $\"1%2F2\"$ of side C for a right triangle to use Pyth theorem:
\n" ); document.write( " $\"h=sqrt%28B%5E2-%28C%2F2%29%5E2%29\"$
\n" ); document.write( " $\"h=sqrt%2860%5E2-%2890%2F2%29%5E2%29\"$
\n" ); document.write( " $\"h=sqrt%283600-2025%29\"$ = $\"sqrt%281575%29\"$ = $\"39.7%3E=40m\"$
\n" ); document.write( "Then, $\"A=%281%2F2%2990%2A40=1800m%5E2\"$
\n" ); document.write( "thank you,
\n" ); document.write( "Jojo\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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