Math - Linear Equations

In this lecture we looked at the linear equation. We also learnt what happens when our lines are horizontal or vertical.

For your challenge, you need to match up the equations to the type of line:

  1. (x^2 / 4) – 3
  2. y = ln(4)
  3. y = x/2 + 2
  4. x = 1

A. Vertical
B. Parabola (not a straight line)
C. Positively sloped
D. Horizontal


1 ( B )
2 ( D )
3 ( C )
4 ( A )

I don’t want to be mean but can something be done for the posts that are challenges responses not hidden (in spoiler brackets or anything)? Even more so when it’s a new topic, next to the official challenge topic.
Because I scroll down to find the official challenge and then I find it between other topics that spoils the answer.
Anyway. Great lessons as usual!

Thanks for the feedback. I’ve passed it on to the powers that be.
From what I’ve seen, the majority of students are adding the spoiler tags, but these aren’t currently being translated to the previews under the videos. I’m not sure if it can be fixed but I’ll continue to create a central thread for each lecture to try and mitigate the problem (Most of the other threads you see where created before the one I added).

Oh ok that explains it. Thanks!

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@garypettie Great content! I am sorry about nit picking here, BUT small detail in that line D is a little too high on the graph. With ln(2) = 0.69 we would expect it to be under the first Y hash. Thank you so much for the hard work and amazing content that is here! I am honestly learning so much!

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I’m glad to hear that you’re enjoying the content so far!

You’re absolutely right. Line D more closely represents y = ln(4) rather than y = ln(2)

Well done for spotting this error, I’m always happy to be corrected and will update the challenge accordingly.

Without any math basics, my brain shouted for the vertical line problem (definition), flip the axes.
Make the Y-ax horizontal and the X-ax vertical and adjust the formula.
Basically rotating it, making a vertical line horizontal …

Creative idea, but not the math solution. :wink:

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@FedPete, you’re actually not that far off and that kind of creative thinking is a powerful tool when it comes to understanding math.

If you consider a horizontal line on an ordinary x-y graph.
The formula for that is, y = 0x + c, which cancels down to y = c.

Now if you flip the axes (so y runs along the horizontal) and graph the exact same horizontal line on your new a y-x graph, then you have x = 0y + c, or x = c.

Finally, you can flip the axes back to the correct x-y orientation but keep the formula the same (x = c), and this converts it from a horizontal line to a vertical one.

So you’re right, it is a creative way to solve the problem and is still a solution based in math.
It’s just solve more geometrically than algebraically.

This just goes to show that there is always multiple ways to tackle problems in math and if you can think about problems differently then you may even come up with a solution that no one has ever thought of before!

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  1. B
  2. D tricky - tossing in an ln to distract from the fact there is no x :slight_smile:
  3. C also tricky - you have to realize that x/2 = 1/2 * x
  4. A

I enjoyed almost getting caught out on this one - had to look more closely

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My results:

  1. B
  2. D
  3. C
  4. A
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1.- B
2.- D
3.- C
4.- A

Why algebra lessons weren’t this fun during school/college? I’ve always loved math since mid school, but having an actual purpose for this equations makes everything so much more interesting.

Here is my response:

1 is B because variable x is to the power of 2 which makes it parabola.

2 is D because it has no variable x so the result will be always the same no matter what variable x is.

3 is C because variable x is to the power of 1 which makes it a line

4 is A because variable x will be always 1 no matter what variable y is.

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1 - B
2 - D
3 - C
4 - A

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  1. b
  2. d
  3. c
  4. c

@u571989, you put down “C” for both (3) and (4). Did you mean to mark (4) as “A” instead?