graphing equations and inequalities

[StrawberryHobo]

How do I graph:
(1) -6y+4x=12
(2) y={-x-2, if "x" is less than 1 and 4, if x" is greater than or equal to 1
(3) y=-3|x|
(4) x-2y>-2

 

[StrawberryHobo]

How do I graph:
(1) -6y+4x=12
(2) y={-x-2, if "x" is less than 1 and 4, if x" is greater than or equal to 1
(3) y=-3|x|
(4) x-2y>-2

I dont need the specific answer to any of them just a quick refresher on how to start them. this is review for me

 

[Yogi]

Pick a value for x, calculate the corresponding value for y, graph the (x,y) point you just found, repeat.

 

[StrawberryHobo]

Pick a value for x, calculate the corresponding value for y, graph the (x,y) point you just found, repeat.

like for number one: is this the answer y=-2 x=3...?

 

[Yogi]

Pick a value for x, calculate the corresponding value for y, graph the (x,y) point you just found, repeat.

Pick x=3.
-6y+4(3)=12
-6y+12=12
-6y=0
y=0

From that we have the point (3,0), graph it.
Now do this process again for a different point and connect the 2 points with a line.

We expect the graph to be a line because the equation can be written as the form Ax+By+C=0 which is why we only need 2 points. If you did not know this fact you would have probably figured out it was a line after 3-4 points or so.

Alternatively you could manipulate the formula to look like y=mx+b and graph using the y-intercept and slope.

 

[StrawberryHobo]

Pick x=3.
-6y+4(3)=12
-6y+12=12
-6y=0
y=0

From that we have the point (3,0), graph it.
Now do this process again for a different point and connect the 2 points with a line.

We expect the graph to be a line because the equation can be written as the form Ax+By+C=0 which is why we only need 2 points. If you did not know this fact you would have probably figured out it was a line after 3-4 points or so.

Alternatively you could manipulate the formula to look like y=mx+b and graph using the y-intercept and slope.

Thanks again!