Not necessarily, the more correct definition is opposite reciprocal slopes.
The example used is how horizontal and vertical lines are parallel. Horizontal lines have a slope of 0, also written as 0/1. However, vertical lines have an undefined slope, which isn't necessarily negative. It has a slope of 1/0, which is undefined. In this case, the reciprocal isn't negative.
In all other cases (1 and -1, 2 and -1/2, etc.) yes, the perpendicular pairs are negative and reciprocal.
For 11, we start by plugging 1 in, getting 2(1)^2+1-5=-2=y
Plugging 1+m instead, we get 2(1+m)^2+1+m-5=2(1+2m+m^2)+1+m-5
= 2+4m+2m^2+1+m-5= 2m^2+5m-2. We have to find the difference between that and -2, so 2m^2+5m-2 -(-2)=2m^2+5m
Differentiating 12, we use the Power Rule to get -6x^2+14, and plugging x=1 into it, we get -6(1)^2+14=-6+14=18
B.

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please mark as brainliest.