Heron's formula

[Suchal Riaz]

What do you mean by anticlockwise? Please elaborate.

u did not know this? answer can come wrong if u dont follow it. this is a very strict rule. corrdinate of each point should be considered x1,y2 then next x2y2 so on untill xn,yn to back x1,y1

plot points roughly then draw arrows that they come back to the point where they started. the direction of the arrows should do anticlockwise:

 

[Saad Mughal]

u did not know this? answer can come wrong if u dont follow it. this is a very strict rule. corrdinate of each point should be considered x1,y2 then next x2y2 so on untill xn,yn to back x1,y1
View attachment 28367
plot points roughly then draw arrows that they come back to the point where they started. the direction of the arrows should do anticlockwise:

No. I didn't and honestly, I've never got an Area wrong. Still. Thanks. I'll see to it.

 

[Suchal Riaz]

btw the lines are not modulus but sign of determinant. the things table inside is a matrix. the answer of it can be negative. but overall answer can only be negative if half of the area is going below the x-axis. like it happens in integrals. negative area in v/t graph may represent displacement is negative(as it is vector)
i do like this. 1/2( | [2X2 matrx] |+ | [2X2 matrix] |+....) where each matrix has x1,y1 as first row and x2,y2 as second row.

 

[Saad Mughal]

btw the lines are not modulus but sign of determinant. the things table inside is a matrix. the answer of it can be negative. but overall answer can only be negative if half of the area is going below the x-axis. like it happens in integrals. negative area in v/t graph may represent displacement is negative(as it is vector)
i do like this. 1/2( | [2X2 matrx] |+ | [2X2 matrix] |+....) where each matrix has x1,y1 as first row and x2,y2 as second row.

Ok Sir ji.

 

[Suchal Riaz]

No. I didn't and honestly, I've never got an Area wrong. Still. Thanks. I'll see to it.

coz u have never find areas of enough polygons where order matters.

 

[Saad Mughal]

coz u have never find areas of enough polygons where order matters.

Well, I've solved the whole Classified only.

 

[Suchal Riaz]

Well, I've solved the whole Classified only.

the classified doesn't have these question
polygons in past papers are pretty simple. and mostly in first quadrant.

(if u see any guy telling u what u don't know, understand that he is internet student and trying to show-off extra knowledge )

 

[Saad Mughal]

the classified doesn't have these question
polygons in past papers are pretty simple. and mostly in first quadrant.

(if u see any guy telling u what u don't know, understand that he is internet student and trying to show-off extra knowledge )

But I'm an internet student as well.
But I don't go into much in detail of what I somehow learned in class.

 

[Suchal Riaz]

But I'm an internet student as well.
But I don't go into much in detail of what I somehow learned in class.

i dont know the level of detail we need. and which class? my class in google chrome

 

[Saad Mughal]

i dont know the level of detail we need. and which class? my class in google chrome

Well, unlike you, I actually did have an Add.maths teacher so.. My class class.

 

[Haris Bin Zahid]

btw the lines are not modulus but sign of determinant.

No. It is infact the modulus sign. Check this: http://www.mathopenref.com/coordtrianglearea.html

 

[Saad Mughal]

I win. Yay.

 

[mohdumar]

I win. Yay.

Yeah cuz even I never got answer wrong with this method. I just put in coordinates in order i.e. A then B then C then D. clockwise or anticlockwise...

 

[Saad Mughal]

Yeah cuz even I never got answer wrong with this method. I just put in coordinates in order i.e. A then B then C then D. clockwise or anticlockwise...

Same here.
But, Suchal has a point.

 

[Suchal Riaz]

Ni

No. It is infact the modulus sign. Check this: http://www.mathopenref.com/coordtrianglearea.html

The boxes in whixh there is two by two matrix is NOT MODULUS
brakcets 1/2[] are actually modulus. But not always. When dealing with vectors on y-axis area can be negative

 

[Iishrak]

View attachment 28346
I hope you understand the drawing, I'm kinda bad at this paint thing.
So, here it is. The Heron Formula, you can use it FOR ANY polygon, just remember that the (1/2) always come in the formula and the first vertice is always repeated by the end. Hope that helps!

i didnt know it was called the heron formula, it's really helpful no doubt

 

[Ahmed Raja]

Haris Bin Zahid are you from beaconhouse islamabad?