How many solutions does the following have?

Y = x - 1
&

y - x = -9

No solution

Step-by-step explanation:

y=x-1 and y-x=-9

1st make sure both equations are in slope intercept form

since the 2nd equation isn't, you change it by adding x to both sides and rewrite it as y=mx+b so

y-x=-9

+× +×

y=×-9

now you have y=x-1 and y=x-9

substitute the y with the other equation

x-1=x-9

subtract x from both sides since you can't have the variable on both sides

now you've got -1 = -9

and since that equation isn't true, it has no solution.