Graphing functions

R

rachelmaddie

Full Member
Joined
Aug 30, 2019
Messages
851
I know that this isn’t exactly precise but I don’t have graphing paper. I’m required to label the function correctly. Is this correct?19648C36-BFB9-45C3-BC9C-A2A23FAC70A5.png7401DFA7-F46C-425D-B30D-4C96C6E91D59.jpeg

y = (x + 1)^2 - 4
 
Can you please check where you placed the vertex?

Also label your axes!
 
rachelmaddie said:
What’s wrong with the vertex?
Click to expand...
Where is your y-axis of the graph? What is the co-ordinate of the vertex according to the given equation? What is the co-ordinate of the vertex according to your graph?
 
The vertex is \((-1,-4)\) however you have drawn as if it is the \(y\)-intercept.
 
Let's back off from your problem and work on plotting points.

Please plot these three points (by hand) on a grid: (-3,0), (-1,-4), (1,0). It will be best if you can use graph paper with an actual grid on it, like this:

1594604280577.png

Just plot those three points, and nothing else.
 
Look at where you placed your vertex. From that point look up to the x-axis and read off the x-value. Do the same for the y-value. Do not look at the point you wrote on your graph. Please post back your answer.
 
The point you plotted are (-4, 0) at the left, (0, -3) at the bottom, and (0, 0) in the middle. None of these are the points I asked for.

Now we have to figure out where you are making your errors.

Here are the three correct points:
FMH123813.png

You seem to be off by 1 in all your coordinates except 0. I've seen students go off by 1 as you did for (1, 0), by starting their counting with 1 at the origin, but I don't see how you got the others. Can you tell me how you chose the location for one of your dots, so we can discuss it? This is a case where I really wish I could watch you in person to see how you count and move your pencil. That's helped me many times in working with students.
 
Dr.Peterson said:
The point you plotted are (-4, 0) at the left, (0, -3) at the bottom, and (0, 0) in the middle. None of these are the points I asked for.

Now we have to figure out where you are making your errors.

Here are the three correct points:
View attachment 20410

You seem to be off by 1 in all your coordinates except 0. I've seen students go off by 1 as you did for (1, 0), by starting their counting with 1 at the origin, but I don't see how you got the others. Can you tell me how you chose the location for one of your dots, so we can discuss it? This is a case where I really wish I could watch you in person to see how you count and move your pencil. That's helped me many times in working with students.
Click to expand...
I see my mistake. I didn’t count the boxes properly and accidentally plotted the wrong points.
 
Dr.Peterson said:
The point you plotted are (-4, 0) at the left, (0, -3) at the bottom, and (0, 0) in the middle. None of these are the points I asked for.

Now we have to figure out where you are making your errors.

Here are the three correct points:
View attachment 20410

You seem to be off by 1 in all your coordinates except 0. I've seen students go off by 1 as you did for (1, 0), by starting their counting with 1 at the origin, but I don't see how you got the others. Can you tell me how you chose the location for one of your dots, so we can discuss it? This is a case where I really wish I could watch you in person to see how you count and move your pencil. That's helped me many times in working with students.
Click to expand...
I corrected my mistake.883F97FF-4E94-41D9-83DE-4BF699FD7E5D.jpeg
 
Dr.Peterson said:
The point you plotted are (-4, 0) at the left, (0, -3) at the bottom, and (0, 0) in the middle. None of these are the points I asked for.

Now we have to figure out where you are making your errors.

Here are the three correct points:
View attachment 20410

You seem to be off by 1 in all your coordinates except 0. I've seen students go off by 1 as you did for (1, 0), by starting their counting with 1 at the origin, but I don't see how you got the others. Can you tell me how you chose the location for one of your dots, so we can discuss it? This is a case where I really wish I could watch you in person to see how you count and move your pencil. That's helped me many times in working with students.
Click to expand...
Is this good?BB218ADD-1A0A-4D86-92C3-0BDC7A3A3289.jpeg
 
Better. But where does your graph cut the y-axis. (Hint. On the y-axis, x=0 so what is y?)
 
You must log in or register to reply here.
Top