First We have to isolate y, moving 7 to the other side , doing so the equation would be
y=-7+3(x-1)
Then we multiply 3 by x and then by -1. doing so the equation would be
y=-7+3x-3
Adding -3 to -7 we get the slope-intercept form
y= -10 + 3x
The answer would be option C.