Question

The line m has a slope of a/b , where a and b are integers. What is the slope of a line that is perpendicular to line m ?

Answer 1

The slope of the perpendicular line is -b/a

Explanation:

Perpendicular lines have slopes that multiply together to equal -1

Let the slope of the perpendicular line be p

a/b * p = -1

Multiply each side by b/a so we can isolate p

a/b * b/a * p = -1 * b/a

p = -b/a

The slope of the perpendicular line is -b/a