What is the measure, in degrees, of the angle marked B?
133
65
68
47

Answer:
[tex]\boxed {\boxed {\sf 133 \ degrees }}[/tex]
Step-by-step explanation:
According to the Exterior Angle Theorem, the exterior angle of a triangle is equal to the sum of the 2 remote and opposite interior angle.
[tex]d=a+b[/tex]
In this triangle, angle B is the exterior angle (d). The two interior angles are 68 degrees and 65 degrees ( a and b).
[tex]\angle B=68 \textdegree +65 \textdegree[/tex]
Add.
[tex]\angle B= 133 \textdegree[/tex]
This can also be solved using triangles and supplementary angles.
The angles in a triangle must add to 180 degrees. We have three angles: 68, 65, and an unlabeled angle we can call x.
[tex]68+65+x=180 \\133+x=180[/tex]
Subtract x from both sides.
[tex]133+x=180-133 \\x=47[/tex]
x is on a straight line with B, so they are supplementary and add to 180 degrees.
[tex]47+ \angle B= 180[/tex]
Subtract 47 from both sides.
[tex]47-47+ \angle B= 180-47\\\angle B= 133[/tex]
Angle B is equal to 133 degrees.