How do you find the slope for x=-4? Algebra Graphs of Linear Equations and Functions Slope 1 Answer smendyka Jan 22, 2017 Because this represents a vertical line where for any value of y the x value will be -4 the slope is undefined. Answer link Related questions What is Slope? How can slope be undefined? How do you calculate slope from a graph? How do you calculate the slope given two points? How does a positive slope differ from a negative slope? How does change in the slope affect the steepness of a line? Why is the slope of a horizontal line is zero? How do you determine the slope of (3, –5) and (–2, 9)? How do you determine the slope of (1/3, 3/4) and (–2, 6)? How do you determine the slope of (2,7) and (7,2)? See all questions in Slope Impact of this question 1824 views around the world You can reuse this answer Creative Commons License