Determine whether the lines are parallel, perpendicular, or neither.
y = 9x + 9 and y = -9x + 9
in y = mx + b, the slop is m
for parallel lines the slopes must be the same
for perpendicular lines the slopes are negative reciprocals of each other.
I see the first slope as +9 and the second as -9
so which fits?
perpendicular
no, its neither
to be perpendicular, if one is +9 the other would have to be - 1/9
To determine whether two lines are parallel, perpendicular, or neither, we need to compare their slopes.
The given lines are in the form y = mx + b, where m is the slope.
For the first line, y = 9x + 9, the slope is 9.
For the second line, y = -9x + 9, the slope is -9.
If two lines have the same slope, they are parallel. If the slopes are negative reciprocals of each other, the lines are perpendicular. If the slopes are neither the same nor negative reciprocals, the lines are neither parallel nor perpendicular.
In this case, the slopes are negative reciprocals of each other. The slope of the first line (9) multiplied by the slope of the second line (-9) equals -81, which is -1 when simplified. Therefore, the lines are perpendicular.