The sum of angles in a triangle add up to 180°, therefore to find the value of x we proceed as follows;
sum of angles in ΔABC will be:
48+(6x-28)+2x=180
putting like terms together we get
48-28+6x+2x=180
20+8x=180
8x=180-20
8x=160
x=160/8
x=20°
hence:
∠B=(6x-28)=6×20-28=92°
∠C=2x=2×20=40°
