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Jack and Jill are trying to find the slope of a line segment connecting two points, (x1, y1) and (x2, y2). Jack uses the formula m = y2 - y1 x2 - x1 . Jill mistakenly uses a different formula, but still gets the right answer. Which formula COULD she have used?

2 Answers

1 vote
The right formula to get the slope is: m =(y₂-y₁)/(x₂-x₁)
But if you right it the other way round m = (y₁-y₂)/(x₁-x₂)

Both give the same the answer but the 1st is the right one
User Artusamak
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Answer:

Slope (
m_(2)) =
((y_(1)-y_(2)))/((x_(1)-x_(2)))

Explanation:

To find the slope of a line which passes through (
x_(1),y_(1)) and (
x_(2),y_(2)) we use the formula

Slope (
m_(1)) =
((y_(2)-y_(1)))/((x_(2)-x_(1)))

Now we will rewrite this formula in another form

Slope (
m_(2)) =
(-(y_(2)-y_(1)))/(-(x_(2)-x_(1)))

=
((y_(1)-y_(2)))/((x_(1)-x_(2)))

If we change the sign of numerator and denominator fraction will remain the same.

Therefore, Slope will remain same and Jill can use this formula to get the value of slope.

User Haylie
by
6.6k points