ax + by = c and dx + ey = f \( \Large \frac{a_{1}}{a_{2}}=\frac{a}{d}, \frac{b_{1}}{b_{2}}=\frac{b}{e}, \frac{c_{1}}{c_{2}}=\frac{c}{f} \) Because, \( \Large \frac{b_{1}}{b_{2}} = \frac{c_{1}}{c_{2}} \) Therefore, \( \Large \frac{b}{e} = \frac{c}{f} \) It represents a pair of parallel lines. Because, \( \Large \frac{a_{1}}{a_{2}} = \frac{b_{1}}{b_{2}} \) Therefore, \( \Large \frac{a}{d} = \frac{b}{e}\) Therefore, system has unique solution and represents a pair of intersecting lines.