Answer:
[tex]\text{m}\angle2=180-140=40\ \ \ [\text{Angle 2 and 140 are angles of straight line. Hence}\\\text{their sum equals 180.]}\\\\\text{m}\angle3=180-150=30[/tex]
[tex]\text{m}\angle1+\text{m}\angle2+\text{m}\angle3=180^\circ\ \ \ [\text{Sum of angles of triangle is 180}^\circ.]\\\text{m}\angle1+40^\circ+30^\circ=180^\circ\\\text{m}\angle1=110^\circ[/tex]
See the image I posted...hope this helps you understand the basic geometry concepts!
