Perpendicular line: line through (4, 6) perpendicular to y = -3x + 3

Gadsilla

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Oct 31, 2018
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Here's what I've done so far:


I'm not sure how to proceed from here, from my understanding I've got to add a constant ?
 
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I'm not sure how to proceed from here, from my understanding I've got to add a constant ?

The problem is

An equation of a line through (4,6) which is perpendicular to the line y = -3x + 3 has slope ____ and y-intercept at ____.

Your work, cleaned up a bit, is

FMH113431.jpg

You have not quite written what I expect you to write:

y = (1/3)x + b

then

6 = (1/3)(4) + b

but I think that's what you intended. Then you solved for b, as I would expect -- but how is 6 - (1/3)(4) equal to 5??

Do the correct arithmetic, and you will have the answer.
 
Here's what I've done so far:

I'm not sure how to proceed from here, from my understanding I've got to add a constant ?
If \(\displaystyle a\cdot b\ne 0\) then any line perpendicular to \(\displaystyle ax+by+c=0\) has the form \(\displaystyle bx-ay+d=0\).
So the first step is ti rewrite your line as \(\displaystyle 3x+y-3=0\).
Can you finish using \(\displaystyle (4,6)\) to find \(\displaystyle d\)
 
Last edited by a moderator:
The problem is
An equation of a line through (4,6) which is perpendicular to the line y = -3x + 3 has slope ____ and y-intercept at ____.

Your work, cleaned up a bit, is

View attachment 10508


You have not quite written what I expect you to write:
y = (1/3)x + b

then
6 = (1/3)(4) + b

but I think that's what you intended. Then you solved for b, as I would expect -- but how is 6 - (1/3)(4) equal to 5??

Do the correct arithmetic, and you will have the answer.

****, I should've used my calculator it's 4.66. How do I plug that ? y = 1/3x+4.66 ? I've got the slope, but I don't know where to go from here to find where it intercepts.
 
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Gadsilla: Did you receive my private message six days ago? Please stop using the gyazo site in this forum. Thank you. :cool:
 
****, I should've used my calculator it's 4.66.
You should not be using your calculator. You should be doing arithmetic with fractions by hand. That way, you'll get the exact value, instead of a rounded approximation (4.66).

I've reviewed your posts in this forum. You have a habit of skipping tutor's questions and not following their suggestions.

Please don't milk us for answers. Make an stronger effort, instead. Like the guidelines say, if you don't understand a reply, ask us about it, and we will guide you further. Agree?

Can you multiply 1/3 by 4? Can you subtract the result from 6, by first getting a common denominator?
 
You should not be using your calculator. You should be doing arithmetic with fractions by hand. That way, you'll get the exact value, instead of a rounded approximation (4.66).

I've reviewed your posts in this forum. You have a habit of skipping tutor's questions and not following their suggestions.

Please don't milk us for answers. Make an stronger effort, instead. Like the guidelines say, if you don't understand a reply, ask us about it, and we will guide you further. Agree?

Can you multiply 1/3 by 4? Can you subtract the result from 6, by first getting a common denominator?

I skip it because I don't understand it. I'm not milking anyone for answers as these are questions I am doing outside of my cyllabus just to keep my knowledge up to date. What would you call my attempt at the question ? Not an effort ?
 
I skip [tutor's questions and suggestions] because I don't understand it.
:idea: If there's anything in a reply that you don't understand, let us know what it is. We can try providing more detail, rewording, or a different approach.

I'm not milking anyone for answers … What would you call my attempt at the question? Not an effort ?
Perhaps, my choice of words was too harsh. What I meant is that, when a first step or two is provided, you imply that you already knew that and ask for the next step, and, after that, you say you got it but then ask how to get the answer.

I would call your attempt 'an effort'. After you get guidedance, try thinking or experimenting more, before giving up too quickly. If you rely on crutches, it'll take longer to stand on your own.
 
****, I should've used my calculator it's 4.66. How do I plug that ? y = 1/3x+4.66 ? I've got the slope, but I don't know where to go from here to find where it intercepts.
It actually rounds to 4.67, but don't use the decimal approximation version. Use the exact value of 14/3.

y = (1/3)x + 14/3

From this you see that the y-intercept is (0, 14/3).

If you want the x-intercept, set y equal to 0.

0 = (1/3)x + 14/3

-14/3 = (1/3)x

(3/1)(-14/3) = (3/1)(1/3)x

-14 = x

Then the x-intercept is (-14, 0).
 
:idea: If there's anything in a reply that you don't understand, let us know what it is. We can try providing more detail, rewording, or a different approach.

Perhaps, my choice of words was too harsh. What I meant is that, when a first step or two is provided, you imply that you already knew that and ask for the next step, and, after that, you say you got it but then ask how to get the answer.

I would call your attempt 'an effort'. After you get guidedance, try thinking or experimenting more, before giving up too quickly. If you rely on crutches, it'll take longer to stand on your own.

If you've been reading the posts as well, like you said you've been doing you'll see that people start being condescending when I ask about explanations regarding questions I don't understand which is why I only ask if I understand it.

Also, I'm not looking for the answer, I'm looking for the way to do it & why.
 
Gadsilla: Did you receive my private message six days ago? Please stop using the gyazo site in this forum.
@mmm4444bot, thank you thank you for that request.
Please continue to do what you can to encourage users to use the attachment feature.
If users can use some sort of 'paint program', then we can be of more help.
 
If you've been reading the posts … you'll see that people start being condescending …
On the contrary, what I see is you becoming argumentative too quickly. Please don't take things so seriously; try to be receptive to constructive criticism without interpreting it as a personal attack.

I'm not looking for the answer, I'm looking for the way to do it & why.
Then we ask that you not skip over suggestions when you don't understand them. If you let us tutor you, our goal is for you to see the way, by doing more of your own thinking. That's how one grows their brain. As long as you're making efforts, we're willing to go over it as many times as it takes. 8-)


Spoon feeding in the long run teaches us nothing but the shape of the spoon. - E. M. Forster
 
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