Explain why is equal to the sum of the measures of the two nonadjacent interior angles. **What is the name of the property?***

Exterior Angle Property

Step-by-step explanation:

Interior Angle :

The angle formed with in the closed boundary of the triangle is called an interior angle.

In the given figure,  α ,  β and γ are interior angles.

Exterior Angles:

The angle formed outside the closed boundary of the triangle is called an exterior angle.

In the given figure,  γ' is an exterior angles.

Sum of the measures of the two non-adjacent interior angles  is EQUAL to  measure of an exterior angle of a triangle.

⇒   α +    β   = γ'

This property is known as " Exterior Angle Property"

Also, here angles  γ and γ' are making a linear pair.

γ +     γ'  =  180°

b

step-by-step explanation:

m∠cdf = 43° , m∠gdf = 114°, m∠gde = 23°, m∠edh = 23° , m∠cdh = 157°

step-by-step explanation:

since, it is given that de bisects the angle gdh ⇒ de divides the angle gdh into two equal angles.

⇒ m∠gde = m∠edh

⇒ 8·x   - 1 = 6·x + 5

⇒ x = 3

so, m∠gde = 8·x - 1 = 23°

and m∠edh = 23°

now, it is given ∠cde is an straight angle so, m∠cde = 180°

⇒ m∠cdf + m∠fdg + m∠gde = 180°

⇒ 43° + m∠fdg + 23° = 180°

⇒ m∠fdg = 114°

again, m∠cde = m∠cdh + m∠edh = 180°

m∠cdh + 23° = 180°

⇒ m∠cdh = 157°