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7.7: Parallel and Perpendicular Lines. LEQ: What are the relationships between parallel and perpendicular lines?. Warmup. Does the graph below suggest a positive, negative, or no relationship?. Warm-up: Sketch the following equations on the same axes using the slope and y- int :.
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7.7: Parallel and Perpendicular Lines LEQ: What are the relationships between parallel and perpendicular lines?
Warmup Does the graph below suggest a positive, negative, or no relationship?
Warm-up: Sketch the following equations on the same axes using the slope and y-int: A) y = 2 x - 2 B ) y = 2 x + 1 C ) y = - ½ x + 2 • What do you notice about lines A & B ? ____________________________ • What do you notice about lines A & C and lines B & C ? _________________________
Conclusion: The slopes of parallel lines are ____________________________. The slope of perpendicular lines are ___________________________ which means that their product equals ________.
Ex 1) Complete the following chart : m of a line m of parallel line m of perpendicular line 3 0
What about… Slopes of 0 or 1? -x…what is the parallel and perpendicular slope?
Ex 2) Write the slope-intercept form of an equation for the line that passes through ( -1 , -2 ) and is parallel to the graph y = - 3 x – 4.
Ex 3) Write the slope-intercept form of an equation for the line that passes through ( 3 , -4 ) and is perpendicular to the line y = 3/2 x + 5.
Ex 4) Write the slope-intercept form of an equation for the line that passes through ( - 3 , -2) and is perpendicular to the graph x + 4 y = 12.