Given that the slope of a line is -1/5, what is the slope of a line that is perpendicular to it?
3 Answers
Slope is 5
Explanation:
The perpendicular to a given slope is its negative reciprocal. This means the fraction is flipped and multiplied by
Explanation:
The perpendicular slope of any original slope is derived by negating the original slope and then "flipping" the fraction. By "flipping" the fraction, I mean find the inverse of the original slope. So for example:
Original slope:
Step 1. Negate the original slope. Remember that a negative of a negative is a positive.
Step 2. "Flip" the fraction, finding it's inverse. Remember that whole numbers can be turned automatically into fractions by placing them over a 1.
More generally, you can always find the perpendicular slope using this formula:
All you have to do is remember and follow the method in the first bit of the explanation.
The rest is supportive expansion and contains the actual solution.
Explanation:
Let the slope (gradient) of the first line be
Then the gradient of the perpendicular line is
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This s true for any straight or curved line graph.
The only difference is that for a straight line it is a constant value but for a curved line it changes to suit the gradient at each and every point
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The given slope is
The gradient of the perpendicular is:
.................................................................................
I left the answer in the format of
For every 1 along you go up 5
The teacher will expect you to write the answer gradient as 5 and not