I’m not quite sure how to solve this any would work!

11. O = (-1, 5/2); 12. H = (1,4)  

Step-by-step explanation:

11. Circumcentre

Your points form the vertices of a right triangle (see image below).

The circumcentre (O) of a right triangle must be at the midpoint of the hypotenuse.

Your hypotenuse has the ends at (-3,4) and (1,1), so

O = ((-3 + 1)/2),(4 + 1)/2))

O = (-2/2,5/2)

O = (-1, 5/2)

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12. Orthocentre

The orthocentre (H) of a right triangle is the vertex at the right angle.

Your right angle is at (1, 4), so

H= (1,4)

the answer would be c:   ax + b = ax + c

step-by-step explanation: