you have to 140 and the other side doesn't have anything so you take 180 and subtract it by 140 180-140=40 so the inside angle is 40 and since you have two angles in the triangle you add them then subtract it by 180 180-(40+35)=105 so now you have the last angle for the inside so then you subtract that angle to get x 180-105=75 so 75=x
