In the diagram, p1p2 and q1q2are the perpendicular bisectors of ab and bc, respectively. a1a2 and b1b2 are the angle bisectors of ∠a and ∠b, respectively. what is the center of the circumscribed circle of δabc?
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Let r = 3. what is the value of r + 58?

Write an inequality and solve each problem. for exercises 11 and 12, interpret the solution.

Anew test for ra is being developed. the test is administered to 750 patients with ra and 750 without ra. for the sake of the question, assume the prevalence of ra in this population is 50%. of the 750 patients with ra, 575 have a positive result. of the 750 patients without ra, 150 have a positive result. what is the positive predictive value of the new test? a575/(575+150) b. 600/(600+ 150) c. 575/(575+125) d. 600/(600+ 125)