Question 9477
Let P = Perimeter of the triangle, which is the sum of three sides


{{{11}}}= first side
{{{(1/5) P}}} = second side
{{{ (1/4) P }}} = third side


{{{11 + (1/5)P + (1/4)P = P }}}


Multiply both sides by the LCD, which is 20.

{{{20*11 + 20*(1/5)*P + 20*(1/4)*P = 20*P }}}
{{{220 + 4P + 5P = 20P }}}
{{{220 + 9P = 20P}}}
{{{220 = 11P}}}
{{{20 = P}}}


Perimeter = 20 centimeters


R^2 at SCC