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#1 2024-03-14 20:44:01

tony123
Member
Registered: 2007-08-03
Posts: 229

5 problems

1.Positive integers m and n satisfy


Find

2.Find the positive integer n such that

3.A trapezoid has side lengths

and
in some order. Find its area

4.A rectangle with integer side lengths has the property that its area minus 5 times its perimeter equals

Find the minimum possible perimeter of this rectangle.

5.For real numbers a, b, and c, the roots of the polynomial

form an
arithmetic progression. Find

Last edited by tony123 (2024-03-14 21:20:40)

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#2 2024-03-14 22:45:03

Bob
Administrator
Registered: 2010-06-20
Posts: 10,298

Re: 5 problems

Thanks Tony,

More (hopefully) later.

Bob

ps. Still stuck with http://www.mathisfunforum.com/viewtopic.php?pid=432520#p432520

Maybe I need a little hint please.


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 smile

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#3 2024-03-26 21:25:46

Bob
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Registered: 2010-06-20
Posts: 10,298

Re: 5 problems

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 smile

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#4 2024-05-08 21:27:26

Keep_Relentless
Member
From: Queensland, Australia
Registered: 2024-05-05
Posts: 43

Re: 5 problems

For Q4, is it the area minus (5 times the perimeter),

As in A - 5P = 2023

Or is it (the area minus 5) times the perimeter,

As in (A - 5) * P = 2023

I'm guessing it's the first one??

Last edited by Keep_Relentless (2024-05-08 23:03:09)


"The most incomprehensible thing about the world is that it is comprehensible." -Albert Einstein.

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#5 2024-05-08 22:36:31

Keep_Relentless
Member
From: Queensland, Australia
Registered: 2024-05-05
Posts: 43

Re: 5 problems

Last edited by Keep_Relentless (2024-05-08 23:02:32)


"The most incomprehensible thing about the world is that it is comprehensible." -Albert Einstein.

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#6 2024-05-08 23:00:39

Keep_Relentless
Member
From: Queensland, Australia
Registered: 2024-05-05
Posts: 43

Re: 5 problems

Oh I forgot the sides are integers.

Last edited by Keep_Relentless (2024-05-08 23:32:24)


"The most incomprehensible thing about the world is that it is comprehensible." -Albert Einstein.

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#7 2024-05-08 23:31:08

Keep_Relentless
Member
From: Queensland, Australia
Registered: 2024-05-05
Posts: 43

Re: 5 problems

I think for Q3 you use Brahmagupta's formula


"The most incomprehensible thing about the world is that it is comprehensible." -Albert Einstein.

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#8 2024-05-09 00:33:02

Keep_Relentless
Member
From: Queensland, Australia
Registered: 2024-05-05
Posts: 43

Re: 5 problems

Regarding Q5, help is needed on finding roots of quintic equations and what's needed to see the answer, thanks smile

Last edited by Keep_Relentless (2024-05-09 00:33:29)


"The most incomprehensible thing about the world is that it is comprehensible." -Albert Einstein.

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#9 Yesterday 18:57:47

Keep_Relentless
Member
From: Queensland, Australia
Registered: 2024-05-05
Posts: 43

Re: 5 problems

Can anyone show how to do Q5??


"The most incomprehensible thing about the world is that it is comprehensible." -Albert Einstein.

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#10 Yesterday 19:36:48

Bob
Administrator
Registered: 2010-06-20
Posts: 10,298

Re: 5 problems

I called the roots a, a+d, a+2d, a+3d and a+4d and expanded that quintic. There were things about the resulting expression that suggested a + b  + c = 9, but I'm not confident that's the correct answer so this one is still on my 'to-do list'.

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 smile

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