To write as a fraction with a common denominator, multiply by .

To write as a fraction with a common denominator, multiply by .

Multiply and .

Multiply by .

Multiply and .

Multiply by .

Combine the numerators over the common denominator.

Move to the left of .

Apply the distributive property.

Multiply by .

Apply the distributive property.

Multiply by .

Multiply by .

Subtract from .

Factor out of .

Factor out of .

Factor out of .

Factor out of .

Simplify y/7-(y-8)/9