Find the angle which the common chord of `x^2+y^2-4x=0` and `x^2+y^2=16` subtends at the origin.

Find the angle which the common chord of x^2+y^2-4x-4y=0 and x^2+y^2=16 subtends at the origin.

Find the angle which the common chord of x^2+y^2-4y=0 and x^2+y^2=16 subtends at the origin.

The common chord of x^2+y^2-4x-4y=0 and x^2+y^2=16 subtends at the origin an angle equal to

The common chord of the circles x^2 +y^2-4x-4y=0 and x^2 +y^2=16 subtends at the origin an angle equal to

The common chord of x^2 + y^2 - 4x - 4y = 0 and x^2 + y^2 = 16 substends at the origin an angle equal to

The common chord of x^2 + y^2 - 4x - 4y = 0 and x^2 + y^2 = 16 substends at the origin an angle equal to

The common chord of x^(2) + y^(2) - 4x - 4y " and " x^(2) + y^(2) = 16 subtends at the origin an angle equal to

The common chord of the circles x^(2)+y^(2)-4x-4y=0 and 2x^(2)+2y^(2)=32 subtends at the origin an angle equal to