Question

The relationship between the slopes of two lines that are parallel is _____________.

The relationship between the slopes of two lines that are perpendicular is _____________.
A line that is parallel to a line whose slope is 2 has slope _____________.
A line that is perpendicular to a line whose slope is 2 has slope _____________.

What must be done to make the graphs of two perpendicular lines appear to intersect at right angles when they are graphed using a graphing utility?

Answer 1

the slopes of 2 lines that are parallel will be the same. the slopes of 2 lines that are perpendicular will have negative reciprocal slopes.
parallel to a line with slope 2 is 2 (because parallel lines have the same slope). perpendicular to a line with slope 2 is -1/2 (the negative reciprocal...to find the negative reciprocal, just flip the slope of the original equation and change the sign)

Answer 2

they are the same slope

they are negative inversees (they multily to get -1)

2

-1/2

use the square viewer (on TI)





The relationship between the slopes of two lines that are parallel is they are the same. The relationship between the slopes of two lines that are perpendicular is they are negative inverses of each other (they multiply to -1).
A line that is parallel to a line whose slope is 2 has slope 2.
A line that is perpendicular to a line whose slope is 2 has slope -1/2.

What must be done to make the graphs of two perpendicular lines appear to intersect at right angles when they are graphed using a graphing utility?