are the following equations an identity?

6y + 9 - y = 7y - 2(y-1)

1 answer

To determine if the given equation is an identity, we need to simplify both sides and determine if they are equal. Let's simplify the equation step by step.

6y + 9 - y = 7y - 2(y-1)

Combine like terms on the left side:
5y + 9 = 7y - 2(y-1)

Distribute the -2 on the right side:
5y + 9 = 7y - 2y + 2

Combine like terms on the right side:
5y + 9 = 5y + 2

We can see that the equation simplifies to 5y + 9 = 5y + 2.

At this point, we notice that the y-terms cancel on both sides of the equation. We are left with 9 = 2, which is not a true statement.

Therefore, 6y + 9 - y = 7y - 2(y-1) is NOT an identity.