Question 155738
{{{A+B=180}}} ---------------> working eqn
{{{B}}} is a supplement of {{{A}}} where {{{A=3B-12}}} ----> {{{highlight(condition)}}}, 3 times its supplement less 12deg.
So go back wworking eqn:
{{{3B-12+B=180}}}
{{{4B=180+12}}} ----> {{{4B=192}}}
{{{cross(4)B/cross(4)=cross(192)48/cross(4)}}}
{{{B=48deg}}}
go back working eqn to get {{{A}}};
{{{A+48=180}}}
{{{A=180-48=132deg}}}
In doubt? go back to the {{{highlight(condition)}}}:
{{{132=3(48)-12}}}
{{{132=144-12}}}
{{{132deg=132deg}}}
Thank you,
Jojo