, ,

Add to both sides of the equation.

Replace all occurrences of in with .

Replace all occurrences of in with .

Simplify .

Simplify each term.

Apply the distributive property.

Multiply by .

Multiply by .

Combine the opposite terms in .

Subtract from .

Add and .

Simplify .

Simplify each term.

Apply the distributive property.

Multiply by .

Multiply by .

Combine the opposite terms in .

Subtract from .

Add and .

Since , the equation will always be true.

Always true

Remove any equations from the system that are always true.

Since , the equation will always be true.

Always true

Always true

Remove any equations from the system that are always true.

Solve by Substitution x-3y=2 , 7x-21y=14 , 3x-9y=6