9514 1404 393
Answer:
-1
Step-by-step explanation:
Solving the given equation for y, we have ...
x -y = 18
y = x - 18 . . . . . add y-18
The coefficient of x is 1. That is the slope of the given line. The desired perpendicular line will have a slope that is the negative reciprocal of this:
m = -1/1 = -1
The slope of the perpendicular line is -1.
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The graph shows you that a line with slope -1 is perpendicular to the given line.
