Angles and lines
We are given the following information
Angle 1 is congruent with angle 2. They have equal measures
Angle CFB measures 124°
Note that angles 4 and F are linear because they are formed by the intersection of two lines.
Linear angles add up to 180°
This means that the measure of angle 4 is:
m angle 4 = 180° - m CFB
m angle 4 = 180° - 124°
m angle 4 = 56°
now note angle 4, 1, and 2 form a straight angle of 180°. This means that
m angle 4 + m angle 1 + m angle 2 = 180°
Since angles 1 and 2 are congruent:
m angle 4 + 2* m angle 1 = 180°
Knowing that m angle 4 = 56°:
56° + 2* m angle 1 = 180°
Subtracting 56°:
2* m angle 1 = 124°
Solving:
m angle 1 = 124° / 2 = 62°
Thus, both angles 1 and 2 measure 62°
Finally, being angles 3 and 4 vertical angles (opposed by a vertex), they are congruent, thus
m angle 3 = m angle 4 = 56°
The solution is given below:
