if 5x -5 =y whats is y?

You need more information...you can't solve for two variables in just one equation, you would need at least two. So let's say you also know that y=x+5 or something, then you can see that you have y=5x-5 and y=x+5. Since both x+5 and 5x-5 equal y, you know that they have to be equal to each other (also known as the transitive property). Then you can solve x+5=5x-5 by adding 5 to each side to get x+10=5x. Next you would subtract one x from each side to get 10=4x. Then you divide each side by 4 to get x=10/4 (ten fourths or 2.5). Now that you know what x is, you can plug it back in to the first equation (5x-5=y) so that you have 5(2.5)-5=y. Then you just have to solve it by multiplying 5 by 2.5 to get 12.5, then subtract the five to get that 7.5=y. But this only works if you can get two equations from the problem. So go back through, and see if you can find another equation. And if you still don't understand it, try emailing your teacher and ask if he/she can help you. Good luck! :)

if x = 1 then y = 0

As for your first equation, what is y? y is 5x-5. that is the answer right there : 5x-5

Variables are not always a number at first. Sometimes the answer is an equation.

if x = 1 then y = 0

I think they both y = 20 x = 5 think 5x = y + 5

if x is one y = 0

1 times 5 minus 5 is 0

ONightingale

20

5x =5X5=25

25=x

-5

=20

5x-5=y

5x-y=5

if 5x-5=Y then Y is 5x-5

5x-5=Y (you cant simplify anymore so thats what Y equals)

Y+5

------ = X

5

if x is 1, y is 0.

Just replace x with 1.