Question

Choose the correct equation for the line shown on the graph?

y
y=-x-4
y=-x-1
y=x-4
y=2x-1
XA

Answer 1

y=-1/4x-1

How to find the slope

To find the slope of the line you need to do the change in y/change in x. This is also known as the rise/run. To do this you count the spaces in between the two points.

In this graph the change in y (rise) is 2. The change in x (run) is 8. Since the line is going down they are negative. The rise/run is -2/8. This can be simplified to -1/4.

Slope: -1/4x

How to find the y-intercept

To find the y-intercept, you need to look at where the line crosses y.

In this graph the line crosses y at -1.

Y-intercept: -1

Final equation: -1/4x-1