Slope and Related Material Flashcards
What is slope?
What other variable is it equal to?
Where is this located in the formula for a line?
Slope is a number that represents the steepness of a line. The ratio of its vertical rise to its horizontal run.
m is another way to represent slope
in y = mx + b, the letter m represents the slope
What is the theorem about parallel lines and slope?
Two nonvertical lines are parallel if and only if their slopes are equal.
This is a biconditional and can be written as: Two lines have an equal slope if and only if the two lines are nonvertical and parallel.
What is the formula for slope?
rise / run → change in y / change in x→ Delta y / Delta X
What does a negative slope look like?
A negative slope goes from left to right
What is positive slope?
Positive slope goes from right to left
What slope does a horizontal line have?
What intercept does a horizontal line cross?
Horizontal lines have a slope of 0
only y - intercept
no x - intercept
What is the slope of a vertical line?
What intercept does it cross?
The slope of a vertical line is undefined because the denominator is 0
only x - intercept
no y - intercept
What is true about lines parallel to horizontal lines?
What is true about lines parallel to vertical lines?
Lines parallel to horizontal lines have a slope of 0
Lines parallel to vertical lines have a slope that is undefined
What is true about two non-vertical lines that are perpendicular?
What is the formula?
Two non-vertical lines are perpendicular if and only if the product of their slopes is -1.
The two lines have slopes that are negative reciprocals of each other. And when the two lines intersect they form 90 degree angles.
When you need to figure out if a triangle is a right triangle (for example) see if the slope of two lines multiplied by each other equal a product of -1.
