Math Is Fun Forum

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Mensuration 1

Hi;
Can anyone help? I have a little trouble solving these. Thanks in advance.

1) Two circles with centres A and B, intersect at X and Y. Show that the common chord XY is the perpendicular bisector of the line AB joining the centres.
2) A room 6 m long, 4 m wide is surrounded by a verandah. Find the width of the verandah if it occupies 24 square metre.

A step by step solution would be very helpful. Thanks.

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Only a friend tells you your face is dirty.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Mensuration 1

Hi;

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Mensuration 1

No I didn't since my understanding of the question is quite unclear.
I did sketch something for 1) though and then I don't know what formula to use to arrive at the answer.

Could you please give a step by step solution of each one you solve? Thanks.

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Only a friend tells you your face is dirty.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Mensuration 1

For 2)

If the piece we have to add all around the house is called x we get:

starting at the top left and going all around clockwise...

Can you solve for an answer?

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Agnishom

Real Member

From: Riemann Sphere

Registered: 2011-01-29

Posts: 24,996

Website

Re: Mensuration 1

No I didn't since my understanding of the question is quite unclear.
I did sketch something for 1) though and then I don't know what formula to use to arrive at the answer.

Could you please give a step by step solution of each one you solve? Thanks.

Draw the radii, draw the chord, draw the connector.

Spot the congruent triangles

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'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Mensuration 1

Dear bobbym, your explanation gives 1 m as the solution like you said before. Thanks.

@Agnishom, pls how exactly is 1) solved?

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Only a friend tells you your face is dirty.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Mensuration 1

Always draw a diagram first.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Mensuration 1

Have drawn the diagram but don't know how to go about the solution.

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Only a friend tells you your face is dirty.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Mensuration 1

Can you do it on your own now?

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Mensuration 1

hi math9maniac

1) Two circles with centres A and B, intersect at X and Y. Show that the common chord XY is the perpendicular bisector of the line AB joining the centres.

Did you mean AB is the perpendicular bisector of XY ?

In any circle, centre A,  draw two radii, AX and AY.  As AX = AY, the triangle AXY is isosceles.  Let M be the midpoint of XY.  What can you say about triangles AMX and AMY ? And hence about the angles AMX and AMY ? ........................

Bob

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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

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Mensuration 1

That gives 2 right-angled triangles and 2 right angles respectively. Thanks. This makes a lot of sense now. I'll work this and see how it turns out. Merci beaucoup.

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Only a friend tells you your face is dirty.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Mensuration 1

je vous en prie

Bob

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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

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Mensuration 1

You speak French. That's nice. How much French do you know?

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Only a friend tells you your face is dirty.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Mensuration 1

Un peu.  Mais je suis un Francophile. 

Bob

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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

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Mensuration 1

D'accord. Vous venez de quel pays? Où est-ce que vous avez appris le français?

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Only a friend tells you your face is dirty.