The right side of the equation of each line is a polynomial. Big Ideas Math Algebra 1 Answer Key Chapter 7 Polynomial Equations and Factoring 7.1 13 a. The absolute value of the difference of the two polynomials represents the vertical distance between points on the lines with the same x-value. Write this expression. b. When does the expression in part (a) equal 0? How does this value relate to the graph?