Math Is Fun Forum

mathland

Member

Registered: 2021-03-25

Posts: 444

Distance of Pass

A soccer player passes the ball from a point
that is 18 yards from the endline and 12 yards from the
sideline. A teammate who is 42 yards from the same
endline and 50 yards from the same sideline receives
the pass. (See figure.) How long is the pass?

I say (12, 18) and (42, 50) are two points on the xy-plane.

I can then use the distance formula for points?

Yes?

Bob

Administrator

Registered: 2010-06-20

Posts: 10,619

Re: Distance of Pass

yes.

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

mathland

Member

Registered: 2021-03-25

Posts: 444

Re: Distance of Pass

yes.

I'm cooking with gas as Richie Cunningham was known for saying on the Happy Days sitcom.

mathland

Member

Registered: 2021-03-25

Posts: 444

Re: Distance of Pass

yes.

What about this set up?

d= √((42-18)^2+(50-12)^2)
d= √(24^2+38^2)
d= √(576+1444)
d= √2020
d is about 44.9 yds

When I plug the points (12, 18) and (42, 50) into the distance formula, I get a different distance for the pass. I get 2•sqrt{481}.

Which is correct?

Thanks

P. S. Did you ban me from this site about two weeks ago?

Last edited by mathland (2021-05-31 14:20:07)

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,876

Re: Distance of Pass

...points (12, 18) and (42, 50)...

It looks like there's an error in one of those points.

---

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

mathland

Member

Registered: 2021-03-25

Posts: 444

Re: Distance of Pass

...points (12, 18) and (42, 50)...

It looks like there's an error in one of those points.

No error. The distances are as given in the question.

Last edited by mathland (2021-05-31 22:14:28)

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,876

Re: Distance of Pass

The measurements given in the question are distances, not 'points' (exact locations) as such, and the error is in their placement within the 'points' notation (ie, the x,y elements in the brackets).

Last edited by phrontister (2021-05-31 22:13:55)

---

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

mathland

Member

Registered: 2021-03-25

Posts: 444

Re: Distance of Pass

The measurements given in the question are distances, not 'points' (exact locations) as such, and the error is in their placement within the 'points' notation (ie, the x,y elements in the brackets).

Care to clarify the error?

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,876

Re: Distance of Pass

...points (12, 18) and (42, 50)...

It looks like there's an error in one of those points.

One of the points has the x & y values the wrong way round.

Edit: I see that since my post #7, in your post #6 you've just edited "The points are as given in the question" to "The distances are as given in the question". Yes, that is the correct understanding here.

Last edited by phrontister (2021-05-31 22:35:25)

---

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

Bob

Administrator

Registered: 2010-06-20

Posts: 10,619

Re: Distance of Pass

hi mathland

Original question: 18 yards from the endline and 12 yards from the
sideline. A teammate who is 42 yards from the same
endline and 50 yards from the same sideline receives ...

You need to be clear about which number is an 'x' and which a 'y'.

I sketched a pitch with the pitch running left to right with one corner as the origin.  Distances from the end line (y axis) are 18 and 42.  Distances from the sideline (x axis) are 12 and 50.

So the correct coordinates are (18,12) and (42,50). And the correct pythag is:

So your original calculation was correct.  But when you used the formula you had the x and y coordinates muddled so no wonder you got a different answer.

When I plug the points (12, 18) and (42, 50) into the distance formula,

Advice for next time:  Always sketch a diagram and mark on the points.  This will reduce your chances of an error.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

mathland

Member

Registered: 2021-03-25

Posts: 444

Re: Distance of Pass

hi mathland

Original question: 18 yards from the endline and 12 yards from the
sideline. A teammate who is 42 yards from the same
endline and 50 yards from the same sideline receives ...

You need to be clear about which number is an 'x' and which a 'y'.

I sketched a pitch with the pitch running left to right with one corner as the origin.  Distances from the end line (y axis) are 18 and 42.  Distances from the sideline (x axis) are 12 and 50.

So the correct coordinates are (18,12) and (42,50). And the correct pythag is:

So your original calculation was correct.  But when you used the formula you had the x and y coordinates muddled so no wonder you got a different answer.

When I plug the points (12, 18) and (42, 50) into the distance formula,

Advice for next time:  Always sketch a diagram and mark on the points.  This will reduce your chances of an error.

Bob

Understood.

Questions:

1. Did you ban me from the site two weeks ago?

2. I have decided to return to chapter 1 in my precalculus textbook. I want a complete review of the course. Are you willing to take the ride with me?

3. How many questions can I post per week to prevent getting banned again?

4. Why would anyone ban me from this site? All I do is contribute to make the site better and more interesting.

5. I still have no clue how to upload pictures here. I need the steps ONE AT A TIME.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,619

Re: Distance of Pass

hi mathland

2. I have decided to return to chapter 1 in my precalculus textbook. I want a complete review of the course. Are you willing to take the ride with me?

I am willing to help but subject to my conditions outlined below.

1. Did you ban me from the site two weeks ago?

Yes.  You were warned in this post:

http://www.mathisfunforum.com/viewtopic … 53#p419353

On 15th May 2021 you posted 17 times.  8 of those posts were not related directly to maths.  I note that no member has responded to any of them.  This shows me that those posts were out of line with what the membership wants.

I am willing to help you to improve your mathematical ability but I was finding it impossible because you were flooding me with new requests faster than I could deal with them, and I was finding it very difficult to find your last post on a topic I was helping with.

After the warning you posted 4 more times in quick succession.  I deleted 3 of the posts and kept one open.  That one requires you to do some work and post some answers.  That still hasn't happened.

4. Why would anyone ban me from this site? All I do is contribute to make the site better and more interesting.

That's your opinion.  From the complaints I have received it is clear that others do not share it.  The ban was temporary as it is my hope that you will post more reasonably in the future.

3. How many questions can I post per week to prevent getting banned again?

I'm a maths teacher with many years of experience.  In class, when starting a new topic, I start by checking the pupils understanding of any preceding work, then launch into an explanation of the new topic,  I intersperse this with many question and answer sessions.  This is so I can check that what I'm saying is understood by the pupils.  I may pick on a particular pupil when doing this if I think he is not paying attention.  Then I set some exercises and check progress as I go around the class.  Finally I set some homework so I can further check that each child has understood what to do.  The results of this help me to decide whether to progress to the next stage or whether to spend more time on the topic.

Look at how many times I check progress.  It's an essential part of the learning process.  The pupils don't learn from me; they learn by doing it themselves (see Galileo quote in my signature)

I have tried to help you on a number of occasions.  This post is the first time I've seen any of your work in response.  It's a good start!  Here's a reminder of what I said on 15th:

(1) Limit your posts to one per day.

(2) Make sure the post is about maths.

(3) Make sure a thread reaches a conclusion where you post a correct answer to your question and thank your helper(s).

Once a conclusion is reached then you are ready to post on a new question.

5. still have no clue how to upload pictures here. I need the steps ONE AT A TIME.

Step 1.  Open an account at www.imgur.com

Say when you have done this and I'll give you step 2.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

mathland

Member

Registered: 2021-03-25

Posts: 444

Re: Distance of Pass

hi mathland

2. I have decided to return to chapter 1 in my precalculus textbook. I want a complete review of the course. Are you willing to take the ride with me?

I am willing to help but subject to my conditions outlined below.

1. Did you ban me from the site two weeks ago?

Yes.  You were warned in this post:

http://www.mathisfunforum.com/viewtopic … 53#p419353

On 15th May 2021 you posted 17 times.  8 of those posts were not related directly to maths.  I note that no member has responded to any of them.  This shows me that those posts were out of line with what the membership wants.

I am willing to help you to improve your mathematical ability but I was finding it impossible because you were flooding me with new requests faster than I could deal with them, and I was finding it very difficult to find your last post on a topic I was helping with.

After the warning you posted 4 more times in quick succession.  I deleted 3 of the posts and kept one open.  That one requires you to do some work and post some answers.  That still hasn't happened.

4. Why would anyone ban me from this site? All I do is contribute to make the site better and more interesting.

That's your opinion.  From the complaints I have received it is clear that others do not share it.  The ban was temporary as it is my hope that you will post more reasonably in the future.

3. How many questions can I post per week to prevent getting banned again?

I'm a maths teacher with many years of experience.  In class, when starting a new topic, I start by checking the pupils understanding of any preceding work, then launch into an explanation of the new topic,  I intersperse this with many question and answer sessions.  This is so I can check that what I'm saying is understood by the pupils.  I may pick on a particular pupil when doing this if I think he is not paying attention.  Then I set some exercises and check progress as I go around the class.  Finally I set some homework so I can further check that each child has understood what to do.  The results of this help me to decide whether to progress to the next stage or whether to spend more time on the topic.

Look at how many times I check progress.  It's an essential part of the learning process.  The pupils don't learn from me; they learn by doing it themselves (see Galileo quote in my signature)

I have tried to help you on a number of occasions.  This post is the first time I've seen any of your work in response.  It's a good start!  Here's a reminder of what I said on 15th:

(1) Limit your posts to one per day.

(2) Make sure the post is about maths.

(3) Make sure a thread reaches a conclusion where you post a correct answer to your question and thank your helper(s).

Once a conclusion is reached then you are ready to post on a new question.

5. still have no clue how to upload pictures here. I need the steps ONE AT A TIME.

Step 1.  Open an account at www.imgur.com

Say when you have done this and I'll give you step 2.

Bob

1. It was you who banned me for silly reasons. I did not see the warning you are talking about. This changes everything.

2.You are willing to help with precalculus subject to your rules. Interesting.

3. Make sure a thread reaches a conclusion. Are you saying threads are left unanswered?

4. My posts have not been offensive. My posts are not unreasonable. My posts are not threatening. Most of my threads in the DARK FORUM are about Christianity. What's wrong with the words of Jesus? In a world that is so cruel, so evil, I expect Bible verses and comments made by famous Christians like John F. Walvoord not to be offensive.

5. You are now saying that uploading pictures will be done one step at a time.

I don't know what to say. Searching for a math forum has not been easy. People dislike me everywhere I post questions.I have been banned from many forums not just this one. I have some serious thinking to do.