The answer would be 8746 ft :)
Answer:
12
Step-by-step explanation:
The measure of the exterior angle at vertex D is: D. 54°
<em><u>Recall:</u></em>
- The exterior angle theorem of a triangle states that the measure of an exterior angle equals the sum of the measures of two opposite interior angles of the triangle.
<em><u>Thus:</u></em>
In ΔDEF, (8x−2)º is an exterior angle at vertex D.
m∠E = (3x−8)° (interior angle)
m∠F = (4x+13)° (interior angle)
<em>Therefore:</em>
(8x−2)º = (3x−8)° + (4x+13)°
8x - 2 = 3x - 8 + 4x + 13
8x - 2 = 7x + 5
8x - 7x = 2 + 5
x = 7
Exterior angle at vertex D = (8x−2)º
= 8(7) - 2
= 54º (option D)
Learn more about exterior angle theorem on:
brainly.com/question/24756010
