Respuesta :

apologiabiology
point slope means
y-y1=m(x-x1)
where the slope is m and a point on the graph is (x1,y1)

we are given
slope=-3
therefor
y-y1=-3(x-x1)
eliminate choices A and D
they gave us point (5,-7)
x1=5
y1=-7

y-(-7)=-3(x-5)
y+7=-3(x-5)
C is answer