3x-9=4x-9 Take the numbers together and the variables together so you’ll get -9+9=0 and 4x-3x =1x or x so x is equals to zero then substitute the zero on both of the equations to get Y= -9 So the answer it has one solution which is -9 at Y and so it’s considered 1 cause (0,9) and 0 is not a solution. Hope it helped:)