Graphing+Lines

media type="youtube" key="2UrcUfBizyw?fs=1" height="385" width="480" 3.2- GRAPHING LINES BY HUTCH OELMAN

You will be given an equation, below is an example: 2x-3y=12

You will plug in different variables for x. If you were to plug in -2 for x, the equation would work out like this:

2(-2)-3y=12 -2-3y=12 -3y=14 y=-4 2/3

By using this equation, you now know that one point on your line will be (-2, -4 2/3. You can continue to plug in numbers for x and find the y coordinate that results from it to find new points on the line. You would then simply connect the dots and your line will be formed.

You can also plug in 0 for y in the equation, and use algebra to find the x value. This will be the y intercept. You can also plug in 0 for x, and use algebra to find the value for y. This will be your x intercept. You can then simply connect the dots between these two dots and your line will be formed.

Example: 2x+3y=122(0)+3y=12 3y=12 y=4 y int=(0,4)

Example: 3x+5y=15 3x+5(0)=15 3x=15 x=5 x int= (5,0)