Answer:
(a.): m∠ ACB = 40°; (b.): m ∠CBA = 25°; (c.): m ∠CAB = 115°
Explanation:
Because Lines AB and DE are parallel, we can use the angle relationships to find the angles.
(For context of the problem, we can label the 40° angle as ∠C and the 155° as ∠B)
(a.) Angles C and ACB are vertical angles, which means they're congruent. Thus m ∠ACB = 40°.
(b.) AB is a straight line and angles B and CBA are supplementary angles. This means their total sum is 180°. We need to subtract angle B from 180 to find m ∠CBA:
(c.) We know that the sum of all the angles is 180°. Thus, we can subtract the sum of angles CBA and CBA from 180 to find the m ∠CAB:
