Mathematics: Post your doubts here!

[Saad the Paki]

Part (v)... help please

 

[misscute406]

hmmm in a regular polygon if all sides are equal all angles will be equal!! It might differ in irregular polygons!!

Hey.. i wanted to know that in a polygon, if 2 sides are equal, will the angles opposite to these be equal as well?
My Name can u help me out with dis?

 

[Saad the Paki]

hmmm in a regular polygon if all sides are equal all angles will be equal!! It might differ in irregular polygons!!

Thats exactly what i was wondering about...

 

[NOneed2speedd]

hey cross multiply

hey cross multiply

Why cross multiply? It have addition side in b/w and both have same denominator
like 4/2 + 4/2 = 8/2

 

[Suhayb.B]

Thats exactly what i was wondering about...

If it's an irregular polygon, and you've got 2 equal sides, the angles are not necessarily equal. This is due to the fact that the other lines making those 2 angles may not be equal. Although, you can create an isosceles triangle this way by drawing a line, this creates 2 equal angles as the sides are equal. Or so I think.. It'd be better if I can draw you a diagram but Im currently out.

misscute406 Are you sure you have the right formula?

 

[misscute406]

If it's an irregular polygon, and you've got 2 equal sides, the angles are not necessarily equal. This is due to the fact that the other lines making those 2 angles may not be equal. Although, you can create an isosceles triangle this way by drawing a line, this creates 2 equal angles as the sides are equal. Or so I think.. It'd be better if I can draw you a diagram but Im currently out.

misscute406 Are you sure you have the right formula?

yeah that formula is right!! that is the formula to find out each interior angle

 

[misscute406]

OMG!! hey that is only for fractions which doesn't have an unknown!!These kind of fractions have an unknown x. If you don't cross multiply then you cannot find the unknown!!

Why cross multiply? It have addition side in b/w and both have same denominator
like 4/2 + 4/2 = 8/2

 

[Suhayb.B]

yeah that formula is right!! that is the formula to find out each interior angle

You mean this formula is right: n(n-2)/180 ? Okay.
Say I have 4 sides (quadrilateral), so n = 4,
4(4-2)/180 = 2 /45. But thats not right as each angle is 90..

The right formula is (n-2)*180 / n

 

[misscute406]

View attachment 53328 Part (v)... help please

sum of the first 'n' interior angle= n(n+1)/2
Step1: Substitute (n-8) in place of n
(n-8)(n-8+1)/2 = (n-8)(n-7)/2

Answer= (n-8)

 

[misscute406]

oops sorry!! it is (n-2)180/n
extremely sorry guyz!! i was a bit confused

You mean this formula is right: n(n-2)/180 ? Okay.
Say I have 4 sides (quadrilateral), so n = 4,
4(4-2)/180 = 2 /45. But thats not right as each angle is 90..

The right formula is (n-2)*180 / n

 

[NOneed2speedd]

OMG!! hey that is only for fractions which doesn't have an unknown!!These kind of fractions have an unknown x. If you don't cross multiply then you cannot find the unknown!!

First time heard it ... i really didn't knew
anyways thanks

 

[misscute406]

First time heard it ... i really didn't knew
anyways thanks

My Pleasure!!

 

[sohaib ul haq]

Hey.. i wanted to know that in a polygon, if 2 sides are equal, will the angles opposite to these be equal as well?
My Name can u help me out with dis?

yes

 

[sohaib ul haq]

thanks! and btw can anyone help me with part 2 of this question https://fbcdn-sphotos-c-a.akamaihd...._=1439786632_c2ea98fc441ef3b7f225741d4352e9bb

can u give all pic of this paper plz [email protected]

 

[Saad the Paki]

sum of the first 'n' interior angle= n(n+1)/2
Step1: Substitute (n-8) in place of n
(n-8)(n-8+1)/2 = (n-8)(n-7)/2

Answer= (n-8)

well... y did u substitue (n-8) in the 1st place..Care to elaborate?

 

[Saad the Paki]

View attachment 53328 Part (v)... help please

The Chill Master ... can u help?

 

[The Chill Master]

well... y did u substitue (n-8) in the 1st place..Care to elaborate?

The Chill Master ... can u help?

(n-8) is is substituted because it's at the position of n.Though I am not sure.

 

[EMMZZZ]

Any tips for Vectors questions? i always seem to get them wrong :/

 

[NOneed2speedd]

Part (c)
(I've never faced any trouble in this kind of questions. .. don't knw why i can't solve this one )

 

[AnonymousX9]

M/J 2010 Paper 42 Question 3(d). What is the method to do it?