What is the sum of the third multiple of four and the third multiple of five

The rows and columns of lattice points in a three-by-three square array are evenly spaced one unit apart. how many distinct triangles with at least one side of length 2 units can be drawn using three lattice points for the vertices?

What are the coordinates of the midpoint of ab? ,1/2) /2,-1) ,-3/2) /2,-2)

For what value of (y) is 3^3/3^y =1/9