The slope-intercept form is:
[tex]y=mx+c[/tex]So first we will find the gradient:
Parallel lines have the same gradient:
[tex]\begin{gathered} g(x)=-2x-6 \\ \text{The gradient from the equation above is -2} \end{gathered}[/tex]So now that we know the gradient of the line as -2, we will then find the equation of the line using the formula below as it passes through (7,4):
[tex]\begin{gathered} y-y_1=m(x-x_1) \\ \text{From (7,4)} \\ x_1=7,y_1=4 \\ y-4=-2(x-7) \\ y-4=-2x+14 \\ y=-2x+14+4 \\ y=-2x+18 \end{gathered}[/tex]