[tex]\huge{\boxed{\text{A.}\ y=-2x+7}}[/tex]
Point-slope form is [tex]y=mx+b[/tex], where [tex]m[/tex] is the slope and [tex]b[/tex] is the y-intercept.
In the given line, the slope is [tex]-2[/tex]. Parallel lines share the same slope, so the answer must have a slope of [tex]-2[/tex] as well.
Point-slope form is [tex]y-y_1=m(x-x_1)[/tex], where [tex]m[/tex] is the slope and [tex](x_1, y_1)[/tex] is a known point on the line.
Substitute in the values, where [tex]m=-2[/tex] and [tex](x_1, y_1)=(3, 1)[/tex]. [tex]y-1=-2(x-3)[/tex]
Distribute the [tex]-2[/tex] to the [tex](x-3)[/tex]. [tex]y-1=-2x+6[/tex]
Add [tex]1[/tex] on each side. [tex]\boxed{y=-2x+7}[/tex]
