3.8 Homework
Parallel lines have the SAME slope.
Example: y = 2x + 1 and y = 2x + 3
Perpendicular lines have OPPOSITE RECRIPRICAL slopes. **Change the sign & flip the fraction!
Example: y = 2x + 1 and y = -1/2x + 3
Neither lines are everything else.
Example: y = 2x + 1 and y = 3x + 1
Are the following lines parallel, perpendicular, or neither?
1. y = 3x + 4 5. y = 4x + 1 9. y = 5x + 2
y = 3x – 5 y = -1/4x – 2 y = -1/5x + 2
2. y = 2x + 1 6. y = -2x + 5 10. y = -4x + 3
y = 2x – 9 y = -2x – 3 y = 1/4x + 6
3. y = -1/3x – 4 7. y = -x + 6 11. y = 9x + 7
y = 3x + 6 y = 6x – 1 y = 5x - 2
4. y = 2/3x + 5 8. y = 2x – 8 12. y = 2/3x - 4
y = -3/2x + 2 y = -1/2x + 4 y = -3/2x + 7
Write the equation of each line in slope-intercept form.
13. A line passing through (4, 2) that is parallel to a line with a slope of -5.
14. A line passing through (8, -2) that is parallel to a line for y = 3x + 5.
15. A line passing through (10, 3) that is perpendicular to a line with a slope of
2
3
.
16. A line passing through (10, -4) that is perpendicular y = 2x + 8
