I'm assuming you mean (a-b)^2 : (a+b)^2
a^2 + b^2 cancel out leaving
-2ab versus +2ab
Therefore (a+b)^2 is +4ab greater.
The median is the middle number. The median of 18 and 16 would be 17.
18 17 16...therefore 17 is the middle number.
(a) correct
(b) The exterior angles of a polygon add to 360°, so the other 8 interior angles add to 160°. Since an exterior angle and its corresponding interior angle add to 180°, the 8 exterior-interior angle pairs we must consider add to 1440°. Thus, the answer is 1280°.
Four 90 degree angles, two pairs of parallel lines, and congruent sides.
Hope this helped!
