Answer:
X=65°
Step-by-step explanation:
Both angles combined is a right angle as indicated by the small square drawn on it, a right angle is always 90° therefore
(x-15°)+40°=90°
combine like terms
x+25°=90°
subtract 25° from each side
x=65°
ABC = 180-120=60
ACB = 180-(40+60)=80
Therefore ECD= 80 as ACB and ECD are vertically opposite angles
the solution is A as that is where the graphs intersect each other