The number of triangles that the four lines y=x+3, y=2x+3,  y=3x+2 and y+x=3 form is

The lines y=x+3,  y=2x+3 and y+x=3 are concurrent at 0,3.Rough sketch of the lines is as shown in the figure.From the figure, three triangles ABD,​ABC and ACD can be formed