Question

Determine mCD
MAB = 88°
m/AED = 80°

Answer 1

arc CD = 112°

Explanation:

the measure of a chord- chord angle is half the sum of the measures of the arcs intercepted by the angle and its vertical angle.

∠ AED and ∠ CED are a linear pair and sum to 180° , that is

80° + ∠ CED = 180°( subtract 80° from both sides )

∠ CED = 100°

then

`(1)/(2)` (CD + AB) = ∠ CED

`(1)/(2)` ( CD + 88) = 100° ( multiply both sides by 2 to clear the fraction )

CD + 88° = 200° ( subtract 88° from both sides )

CD = 112°