You can put this solution on YOUR website! You mean given a "point" and a slope:
( 7, -3 ) m= -4/7
.
Substitute into the "point-slope" form:
y - y1 = m(x - x1)
y - (-3) = (-4/7)(x - 7)
y + 3 = (-4/7)x + 4
y = (-4/7)x + 1 (this is what they're looking for)