Answer:
m∠5 = 75°
Explanation:
Transversal 'a' crosses parallel lines 'l' and 'm' creating corresponding angles 1 and 5. Corresponding angles are congruent.
The measure of angle 1 is given as 75°. Congruent angle 5 will have the same measure.
∠5 = 75°
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Additional comment
Angle 2 is an alternate interior angle with respect to transversal 'b' and angle 4. It is congruent to angle 4.
∠2 = 50°
Angles 1, 2, and 3 together form a straight angle of 180°. That means ∠3 is ...
∠3 = 180° -75° -50° = 55°