Answer: 20133333322
Step-by-step explanation: I just did it thx
Answer:
A(2,2)
Step-by-step explanation:
Let the vertex A has coordinates 
Vectors AB and AB' are perpendicular, then

Vectors AC and AC' are perpendicular, then

Now, solve the system of two equations:

Subtract these two equations:

Substitute it into the first equation:

Then

Rotation by 90° counterclockwise about A(2,2) gives image points B' and C' (see attached diagram)
3x - 18 = 42
3x = 42 + 18
3x = 60
x = 60/3
x = 20