You should get: y=-x+1. The slope is -1, which is implied because the you don't need the one in front of the x.
Slope-intercept form:
y = mx + b
"m" is the slope, "b" is the y-intercept (the y value when x = 0)
Since you know m = -1 and b = 1, you can plug it in:
y = -1x + 1 or y = -x + 1
