Question

Which statement is true about the graphs of the two lines y= -8x - 5/4 and y= 1/8 x + 4/5?

Answer 1

The lines are perpendicular

Explanation:

If we have two lines of equations:

`y = nx + v` (1)

`y = mx + b` (2)

Where n is the slope of the line (1) and m is the slope of the line (2)

Then by definition it is fulfilled that if
`n = -(1)/(m)` means that the lines (1) and (2) are perpendicular

In this case the lines are:

`y= -8x - (5)/(4)` (1)

`y= (1)/(8)x + (4)/(5)` (2)

Observe that:
`n=-8` and
`m=(1)/(8)`

Then it is fulfilled that
`n = -(1)/(m)` because:

`n =-(1)/((1)/(8))`

`n = -8`

Therefore the lines are perpendicular