document.write( "Question 274244: what is the third side of a triangle if one side measures 10 cm, the second measures 15 cm and the perimeter is 45cm? \n" ); document.write( "
Algebra.Com's Answer #200187 by bmckenzie40(10)\"\" \"About 
You can put this solution on YOUR website!
The perimeter of the triangle is the total of all 3 sides. If one side is 10 cm, and a second side is 15 cm's, then the total of the 2 sides is
\n" ); document.write( "15 cm + 10 cm = 25 cm
\n" ); document.write( "so if the perimeter is 45 cm, then you have to subtract the total of the other two sides from the perimeter
\n" ); document.write( "45 cm - 25 cm = 20 cm.
\n" ); document.write( "therefore the length of the third side is 20 cm.\r
\n" ); document.write( "\n" ); document.write( "I hope this helps
\n" ); document.write( "
\n" ); document.write( "
\n" );