Answer:
Convex, since none of the angles are greater than 180°
Geometric mean is the square root of the product of the two numbers:
Using addition
x-y+1/2x+y=1+5
x+1/2x+0y=6
3/2x=6

3x=12
x=4
Using the value of x
x-y=1
4-y=1
y=3
With x as 4 and y as 3, their product is 12
And can be written as (4,3)
This is simple, for the problem to be true the two things would have to = the same thing so X = 6, 6/3 = 6/3
Clean up the equation with x first and x=12.
Substitute this value in to the other equation to solve for y.
You should get a solution of (12,-8)