Why does it make sense to describe an equation that has infinitely many solutions as an identity?

the slope of the line is 60

one point on the line is (40,10)

step-by-step explanation:

in the equation outside the parenthesis the equation always tells you the slope. in this case it is 60.

in the parenthesis is also says 40 which is x because it is near the x and 10 is y because it is near y.

i think it will be zero as slope has a formula of difference between initial and final distance divided by itz time interval