Question 282697
{{{3a-12a+8a-9b-7b+8b-11b+80}}} add like terms
{{{3a-12a+8a=-1a}}}
{{{-9b-7b+8b-11b=-19b}}}
{{{80=80}}}
{{{highlight (-a-19b+80)}}}

________________

 3x(1+2+5+9)={{{3x+6x+15x+27x=51x}}}
+
(3y-9y+4x-12x)={{{-6y-8x}}}
={{{51x-6y-8x=highlight(43x-6y)}}}