## Algebra 1: Common Core (15th Edition)

(3,5)(-1,3)(7,7) We find the rate of all three points by using the slope formula ($\frac{b1−b2}{a1−a2}$); GH=$\frac{5-3}{3-(-1)}$=$\frac{2}{4}$=$\frac{1}{2}$ HI=$\frac{3-7}{-1-7}$=$\frac{-4}{-8}$=$\frac{1}{2}$ They both have the rate of $\frac{1}{2}$ so they are the same line.