Question

A line has this equation: y=-3x+7

Write an equation for the parallel line that goes through (-4,-8)

Answer 1

Given:

The equation of line is
`y=-3x+7`.

A line is parallel to given equation and passes through the point (-4,-8).

To find:

The equation of parallel line.

Solution:

The equation of a line is

`y=-3x+7`

On comparing this equation with
`y=mx+b`, we get

`m=-3`

So, slope of given line is -3.

We know that, slopes of parallel lines are equal. It means, the slope of the parallel line is also -3.

The parallel line passes through (-4,-8) and having slope -3. So, the equation of line is

`y-y_1=m(x-x_1)`

`y-(-8)=(-3)(x-(-4))`

`y+8=(-3)(x+4)`

`y+8=-3x-12`

`y=-3x-12-8`

`y=-3x-20`

Therefore, the equation of parallel line is
`y=-3x-20`.