Question

Line t passes through points (10, 1) and (2, 6). Line u is perpendicular to t. What is the slope of line u?

Answer 1

Let's find the slope for line t first.

We can use the given points 2,6 and 10,1 to find the slope using the slope formula.

$\frac{y.2 - y.1}{x.2 - x.1} = m$

1 - 6 / 10 - 2

-5/8

The slope is -5/8.

Because we know the slope of this line, we can find the slope of the next line instantly, as they are perpendicular.

When a slope is perpendicular to another, it is equal to the negative reciprocal.

Negative reciprocal of -5/8 = 8/5

The slope of line u is 8/5