How do you graph 6x+3y=9 by plotting points?

1 Answer
Dec 19, 2017

See a solution process below:

Explanation:

To graph a linear equation you just need to plot two points. First, solve for two points which solve the equation and plot these points:

First Point: For x = 0

(6 * 0) + 3y = 9

0 + 3y = 9

3y = 9

(3y)/color(red)(3) = 9/color(red)(3)

y = 3 or (0, 3)

Second Point: For y = 1

6x + (3 * 1) = 9

6x + 3 = 9

6x + 3 - color(red)(3) = 9 - color(red)(3)

6x + 0 = 6

6x = 6

(6x)/color(red)(6) = 6/color(red)(6)

x = 1 or (1, 1)

We can next plot the two points on the coordinate plane:

graph{(x^2+(y-3)^2-0.025)((x-1)^2+(y-1)^2-0.025)=0 [-10, 10, -5, 5]}

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

graph{(6x + 3y - 9)(x^2+(y-3)^2-0.025)((x-1)^2+(y-1)^2-0.025)=0 [-10, 10, -5, 5]}