The equation of a line which has the slope m and passes through the point A(x1,y1) has the formula:
y-y1=m(x-x1)
in your case m= -5 ; A(x1;y1)=(1;-1)
y-(-1)= -5(x-1)
y+1= -5(x-1)
answer is c
You combine like terms like 8y+13y which gives you 21y and don't forget the -5x so your simplified equation would end up being A. 21 - 5x
