Graphing Lines, Parallel & Perpendicular Lines

1 Graphing Lines , Parallel & Perpendicular Lines This worksheet will cover two methods for Graphing a line . One method is to find the intercepts and the second method is to use the slope and a point on the line . The x-intercept is found by setting 0y= and solving for x. The y-intercept is found by setting 0x= and solving for y. Each intercept represents a point on the line . Graph each intercept and connect the dots. Example 1: Graph the line 236xy = by finding the intercepts. Solution: First, we must find the intercepts. Let 0y=. ()23 06, 26,3xxx ===. The x-intercept is ()3, 0.

2 Let 0x=. ()2 036,36,2yyy = == . The y-intercept is ()0, 2 . Example 2: Graph the line that has slope 12m= and passes through the point ()2, 1 . Solution: To graph the line , we must start at the point ()2, 1 . Since the slope is 12, this means we will move 1 unit up from the point ()2, 1 , and 2 units to the right. Parallel and Perpendicular Lines Parallel Lines are Lines that never intersect and whose slopes are equal. Perpendicular Lines make a right angle at their intersection point and their slopes are negative reciprocals. In order to decide if two Lines are Parallel , Perpendicular , or neither, you must first solve each equation for y to compare the slopes.

3 Practice Problems Find the intercepts and sketch the graph of each line : 1. 22xy+= 2. 36xy = 3. 42xy = 4. 23xy + = 5. 21xy+ = 6. 3412xy = Given a point and the slope , graph the line : 7. ()13, 1 ,2m= 8. ()1, 1 ,2m = 9. ()2, 3 ,0m = 10. ()24, 1 ,3m = 11. ()40, 0 ,3m= 12. ()2, 3 , is undefinedm Decide if the pair of Lines are Parallel , Perpendicular , or neither. 13. 323321xyxy = = 14. 2346xyxy+ = = 15. 3439yxxy= = 16. 252xyyx+ == 17. 3233yxxy= + = 18. 3533xyyx+= =+