The slope-intercept form is , where is the slope and is the y-intercept.

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 .

Simplify each term.

Divide by .

Dividing two negative values results in a positive value.

Reorder and .

Rewrite in slope-intercept form.

Write in y=mx+b Form x-3y=21