It's asking to find X

50 degrees

Step-by-step explanation:

the middle angles are vertical (equal to eachother) so you just have to do 180-80=100 and divided by two is fifty

Showing fractions can be expressed in model and number line.
Using a model, you have to draw the number of parts (denominator) and shade the number of parts (numerator).

Using a number line, the line starts from 0 to the number of the denominator. You put a marker to the number that is the same as the numerator.

Both model and number line use the value of the numerator and denominator. What makes them different is how they are presented. Model can easily be understood compared to number line.