Solve for the variable then find the missing angle.
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Answer:
Step-by-step explanation:
40+40=3x+20(sum of two interior opposite angle is opposite to the exterior angle formed)
=80=3x+20
=80-20=3x
=60/3=x
=20=x
substitute the value of x
=3x+20
=3*20+20
=60+20
=80
v+71=107 degree(sum of two interior opposite angle is equal to the external angle formed)
=v=107-71
=v=36 degree