,

Subtract from both sides of the equation.

Subtract from both sides of the equation.

Divide each term by and simplify.

Divide each term in by .

Cancel the common factor of .

Cancel the common factor.

Divide by .

Simplify each term.

Divide by .

Move the negative in front of the fraction.

Find the Intersection (and) x+y=180 , 3x+2y=480