Verified answer

When you have slope, I prefer to use y = mx + b where m is the slope and b is the y-intercept.

Plug in m, x, and y to find b.

(-5) = (-1)(1) + b

You find that b = -4.

Now you want standard form, so plug it back into y = mx + b and shape it as you want.

Y = (-1)x + (-4)

Move x over and you get:

Y + x = -4

x+y=-4