Question

How do you graph `x + 4y = -4` by plotting points?

Answer 1

See a solution process below:

Explanation:

For a linear equation we can plot two points and then draw a line through the points to graph the line.

For `x = 0`

`0 + 4y = -4`

`4y = -4`

`(4y)/color(red)(4) = -4/color(red)(4)`

`y = -1` or `(0, -1)`

For `y = 0`

`x + (4 * 0) = -4`

`x + 0 = -4`

`x = -4` or `(-4, 0)`

We can now plot the two points on the graph:

graph{(x^2+(y+1)^2-0.025)((x+4)^2+y^2-0.025)=0}

Now we can draw a line through the points to graph the line:

graph{(x+4y+4)(x^2+(y+1)^2-0.025)((x+4)^2+y^2-0.025)=0}