Suppose ΔDEF has an exterior angle at vertex D. The measure of the exterior angle is (8x−2)º
, m∠E=(3x−8)°
, and m∠F=(4x+13)°
. What is the measure of the exterior angle at vertex D?

Which statements are true? check all that apply. the line x = 0 is perpendicular to the line y = –3. all lines that are parallel to the y-axis are vertical lines. all lines that are perpendicular to the x-axis have a slope of 0. the equation of the line parallel to the x-axis that passes through the point (2, –6) is x = 2. the equation of the line perpendicular to the y-axis that passes through the point (–5, 1) is y = 1.