Quick question. Point-Slope. Thanks

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In summary, the conversation was about a Point-Slope question where the given point was (4, -3) and the slope was m = -2. The solution involved converting the equation to slope-intercept form, y = mx + b, and then to standard form, Ax + By = C, by adding 2x to both sides. The final part of the problem involved understanding the properties of equations and determining the correct form for the answer.
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nukeman
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**Quick question. Point-Slope. Thanks!

Homework Statement



Ok i get all of it, except that last part. Here ill show you. Point-Slope question.

(4, -3), m = -2

so...

y + 3 = -2(x - 4) which then becomes y+3 = -2x + 8)

Then...

subtract 3 from y + 3, and then do it on other side

which then gives you:

y = -2x + 5

Now, I don't get this final part. It says that you go y + 2x, and then -2x + 2x

which gives you: 2x + y = 5

I don't get why and how you do that last part? Can anyone please explain?


Homework Equations





The Attempt at a Solution

 
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Take a look at what eumyang wrote about the properties of equations in post 6 of this thread.

Rather than repeat what he wrote, it would be better if you took a closer look at that.
 
  • #3


Also, you have to be mindful of which form the answer needs to be in. You didn't specify this in your problem, but I'm guessing that it was supposed to be in standard form, because you say at the end
[tex]2x + y = 5[/tex]
which is the standard form of the equation of a line (Ax + By = C). That would be the reason why one would add 2x to both sides in the last step.

If instead you stopped at
[tex]y = -2x + 5[/tex],
then you would have the answer in the wrong form (the above is slope-intercept form). If I were grading this I would have given partial credit because you didn't follow directions.


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Related to Quick question. Point-Slope. Thanks

What is a quick question?

A quick question is a question that can be answered quickly and concisely.

What is point-slope?

Point-slope is a method used in algebra to find the equation of a line given a point on the line and the slope of the line.

Why is point-slope useful?

Point-slope is useful because it allows for the quick and easy calculation of the equation of a line, which can be used to solve a variety of real-world problems.

How do you use point-slope?

To use point-slope, you need to know the coordinates of a point on the line and the slope of the line. Then, you plug these values into the point-slope formula, which is y - y1 = m(x - x1), where (x1, y1) is the given point and m is the slope.

Are there any other methods for finding the equation of a line?

Yes, there are other methods such as slope-intercept form and standard form. However, point-slope is often preferred for its simplicity and versatility.

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