Really confused can someone

a is inversely proportional to b. if a=7.2 when b=-4 , what will a equal when b=6 ?

Acircle has a circumference of 28.36 units what is the diameter of the circle

What will the graph look like for a system of equations that has no solution? a. the lines will be perpendicular. b. the lines will cross at one point. c. both equations will form the same line. d. the lines will be parallel.

If 2(a^2+b^2)=(a+b)^2 then, > a+b=0, > ab=0, > a=b, > 2a=b