Circumcenter of a triangle

I searched through the forum and found some threads about this, but it seems like I'm doing everything write but I'm getting an unreasonable answer.

The problem: Given triangle ABC with A(1,3) B(7,-3), and C(9,5), find the circumcenter of the triangle.

Here is what i did. I found the slope of AB which is -1 so the perp slope is 1. The slope of AC is 1/4 so the perp slope is -4.

Then i found the midpt of AB and I got (4,0) and named it as point D. Next, the midpt of AC is (5,4) and I named it E.

I wasn't too sure of this step. But i set up these two formulas: y = x - 4 (i found the y-intercpt using point D), and y = 5x + 24 (using pt E).

Then I set up a system: x-4 = 5x+24 and got x=-7 and substituted it for the first formula and got y=-11. So i got (-7,-11) as the answer.

The triangle is acute and this point if completely off the triangle, and im pretty sure its wrong.

any help is appretiated