Step-by-step explanation: angle on a straight line equals=180
(a) x+2x+3x =180
(b) 6x=180 (divide both sides by the coefficient of x i.e 6)x
x=180divide by 60
x =30
(c) now we know the value of x substitute it to get the largest value
x+2x+3x =180
30+2(30)+3(30)=180
30+60+90=180
therefore the largest angle is 90 degrees