Problem Solving (PS) | Re: In the figure above, if m is parallel to n, and a = 40, then b + c + d

from the figure above it is clear :
b=c

Also b=d ( angle made by a line on parallel lines)

also d=e
combining all three equations
b=c=d=e--------------------- equation (A)


also from the figure a+b=180 =>b=180-40=140
b+c+d+e=4 b (using equation (A)
b+c+d+e=4*140=560

hence
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