[tex]\begin{gathered} \Rightarrow x_1=-21,y_1=-64,x_2=-15,y_2=-48 \\ equation\text{ of line,} \\ (y-y_1)=\frac{y_2-y_1}{x_2-x_1}(x-x_1) \\ (y+64)=\frac{-48+64}{-15+21}(x+21) \\ (y+64)=\frac{16}{6}(x+21) \\ 6y+384=16x+336 \\ 16x+336-384=6y \\ 16x-48=6y \\ 16x=6y+48 \\ 8x=3y+24 \\ x=\frac{3y}{8}+3 \\ So,\text{ the x-intercept is 3.} \end{gathered}[/tex]
