How do you find the slope of a line parallel to the graph of each question y=3x-8?

1 Answer
Apr 1, 2015

Parallel lines have the same slope. Think slope as the angle between the line and the x-axis. So it makes sense that the slopes have to be equal.

y is the line with a slope of 3.

The standart form formula is ax+by=c.

The slope is: -a/b

If you can't remember this, you can calculate the slope by selecting two random points on the line y.

A = (0,-8)
B = (1,-5)

The slope is: (-8 - (-5))/(0-1) = 3

So any line with slope 3 is parallel to the line y (accept y itself, it is called coincident line)

So we can say this:

A line is parallel to another if and only if their slopes are equal.