# line passing through

#### alysha230893

Line passing through (-4,7) and (1,-3)

#### jgv115

Use the 2 point formula:

$$\displaystyle \frac {y-y_{1}}{x-x_{1}} = \frac {y_{2}-y_{1}}{x_{2}-x_{1}}$$

#### alysha230893

does it matter where i put the numbers

#### Cthul

does it matter where i put the numbers
No, it does not as long as it follows the rule.
Say you subbed $$\displaystyle y_2$$ with 7
$$\displaystyle y_2$$
Then the numerator must be $$\displaystyle x_2$$ from the same point you subbed $$\displaystyle y_2$$ first, in this case, it has to be -4.

Regardless which way you put which points in first, you will always get the same answer.

$$\displaystyle \frac{7--3}{-4-1}=-2$$

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$$\displaystyle \frac{-3-7}{1--4}=-2$$

To refrain from getting confused, label the points.
$$\displaystyle (-4,7)$$ and $$\displaystyle (1,-3)$$
$$\displaystyle (x_1,y_1)$$ and $$\displaystyle (x_2,y_2)$$

or

$$\displaystyle (-4,7)$$ and $$\displaystyle (1,-3)$$
$$\displaystyle (x_2,y_2)$$ and $$\displaystyle (x_1,y_1)$$

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