[tex]\text{Given that,}~~(x_1,y_1) = (-1,3)~ \text{and slope,}~ m = 3\\\\\text{Equation of line,}\\\\~~~~~~~y-y_1 =m(x-x_1)\\\\\implies y -3 = 3(x+1)~~~~~~~~~~;[\text{Point-slope form}]\\\\\implies y-3 = 3x +3 \\\\\implies y = 3x +3 + 3\\\\\implies y = 3x +6~~~~~~~~~~~~~~~~~;[\text{Slope-intercept form}][/tex]
