How do you find the slope given (a,3) and (3,a)?

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Answer 1 · 2016-09-09T17:17:13

The slope is $- 1$ $-1$

Slope of line passing through $(x_{1}, y_{1})$ $(x_1,y_1)$ and $(x_{2}, y_{2})$ $(x_2,y_2)$ is

$\frac{y_{2} - y_{1}}{x_{2} - x_{1}}$ $(y_2-y_1)/(x_2-x_1)$

Hence, slope of line given $(a, 3)$ $(a,3)$ and $(3, a)$ $(3,a)$ is

$\frac{a - 3}{3 - a}$ $(a-3)/(3-a)$

= $\frac{a - 3}{- (a - 3)}$ $(a-3)/(-(a-3)$

= $- 1$ $-1$

Answer 2 · 2016-09-09T17:19:53

$m = - 1$ $m = -1$

The formula for slope is $m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}$ $m = (y_2-y_1)/(x_2-x_1)$

$m = \frac{3 - a}{a - 3}$ $m = (3-a)/(a-3)$

Using a "switch-round" technique by dividing the numerator by a common factor of $- 1$ $-1$ we get

$m = \frac{- (a - 3)}{(a - 3)}$ $m = (-(a-3))/((a-3))$

$m = - 1$ $m = -1$