Answer :
[tex]\begin{gathered} \text{The equation is y=-3x+7} \\ So,\text{ The line equation is y=mx+C} \\ \text{Here, m is the slope and C is intercept of y.} \\ So,\text{ compare the both equation.} \\ C=7 \end{gathered}[/tex]
Thus, y-imtercept is 7.