6. (25 points) Use implicit differentiation to find an equation of the tangent line to tan(y - x) = 3y + 3x at the point (7, 0). 7. (25 points) Rocky is painting a square on the floor of his apartment to separate his territory from Goose's. The square, without its border, is 9 square feet. The border is 6 inches wide. Use differentials to estimate the amount of paint (in square feet) Rocky will need to paint the border. Be sure to use differentials to find an estimate; do not find the actual amount