Answer:
(3,0)
Step-by-step explanation:
Let, coordinate of point A' is (x,y).
Since, A' is the symmetric point A(3, 2) with respect to the line 2x + y - 12 = 0.
So, slope of line containing A and A' will be perpendicular to the line 2x + y - 12 = 0 and also their center lies in the line too.
Now, their center is given by :

Also, product of slope will be -1 .( Since, they are parallel )

x = 2y - 1
So, 
Also, C satisfy given line :

Also,

Therefore, the symmetric points is
.
The answer is 10 because its in the tens place
Area of the sheet used to make the tank = total surface area of the cylinder = 2
r(r+h) = 2 x 22/7 x 63 x 263 = 104148 sq. cm.