Answer:
[tex]3x=78+(x-2)[/tex]
Step-by-step explanation:
The complete question in the attached figure
we know that
The Triangle Exterior Angle Theorem states that: An exterior angle of a triangle is equal to the sum of the opposite interior angles.
In this problem
[tex]3x=78+(x-2)[/tex]
solve for x
[tex]3x=76+x\\3x-x=76\\2x=76\\x=38^o[/tex]
