Question 26. Please help. I would appreciate it if you could explain your steps as well, thanks

Step-by-step explanation:
As angle BAD is a right angle (90°), angles BAC and CAD must sum up to 90°.
Therefore angle CAD = Angle BAD - Angle BAC
= 90° - (x + 20)°
= (70 - x)°
Hence the answer is G.