Can someone answer these three questions?

7 is C this is because if you pluge the x value into the equation and it gives you the y value associated with it for all the points, then it is the correct equation.

8 is A and this is the same principle

9 is C because b = 6h-3 and put this in the equation for a triangle and you get 1/2 (6h-3)h and put into one equation is (6h^2 - 3h)/2

A and b have the greatest common factor 4, so suppose a=4x, b=4y
the least common multiple of 4x and 4y is 4xy, and 4xy=48, so xy=12
ab=4x*4y=16xy=16*12=192

(the integers are either 4 and 48 or 12 and 16, but that's not what is being asked here.)