How do you solve Q6.)?

Both diameters pass through the center of the circle at the same value of x, so you can treat it like a system of equations: 2x+3=3x+2
so x=1, and, plugging x=1 back into either equation, y=5. So the center of the circle is (1,5).

Since the circle passes through (0,0), you can then use distance formula: d=√( [x2-x1]2 + [y2-y1]2 )
Plugging in your two points, you have d= √( [1-0]2 + [5-0]2 ) = √26. So the distance between the center and outer edge (i.e. radius) of the circle is the square root of 26.

The area of a circle can be found with A=πr2. Plugging in the radius, A=π(√26)2=26π. The answer is C.

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