what is the equation of the line that is perpendicular bisector of a segment with an endpoints at (1,1) and (9,7)

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

The line containing the midpoints of the legs of right triangle abc where a(-5,5), b(1, 1), and c(3, 4) are the vertices.

Which measure is equivalent to 110 ml? 0.0110 l 0.110 l 1.10 l 11,000 l