I think i am doing this right i am not sure. First you need to add up all the sides (100+38+22+15) it would equal 175 then you need to subtract it from 360 and get the missing value (x) then the answer would be 185
Standard form is y=mx+b, where m is the slope and b is the y intercept, substitute to find y=3x+3.
Hope this helps!