Question

Consider the line 4 x + 9 y = 8 . What is the slope of a line parallel to this line? What is the slope of a line perpendicular to this line?

Answer 1

Parallel line: -4/9 Perpendicular line: 9/4

Explanation:

This linear equation is written in standard form: Ax + By = C. First, we isolate the y variable to get the equation: y = -4/9x + 8/9. Now we notice that the slope of this line is -4/9. Parallel lines have the same slope, so the slope of the line parallel to this one is also -4/9. The slope of a perpendicular line is the negative reciprocal of the slope of this line, so the slope of a perpendicular line is 9/4.