Question 75913
Side 1 = 3x+7
Side 2 = 4x-9
Side 3 = 5x+6
P = S1 + S2 + S3
{{{ P = 3x+7 + 4x-9 + 5x+6 }}}
Add the 'x' values
{{{ P = 12x +7 -9 +6 }}}
Add constant terms
{{{ P = 12x + 4 }}}