GPREP Co-ordinate geometry
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pls chk attached scrshot
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Use the Area of triangle formula
1/2 mod( ( X1-X2)* (Y2-Y3) - (Y1-Y2)( Y2-Y3))
there fore
1/2 mod ( -4* (-4) - (-3)*3 )
1/2 mod (25) = 12.5
hope its clear...
1/2 mod( ( X1-X2)* (Y2-Y3) - (Y1-Y2)( Y2-Y3))
there fore
1/2 mod ( -4* (-4) - (-3)*3 )
1/2 mod (25) = 12.5
hope its clear...
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Thats actually the formula for area of the triangle when 3 points are given in cood geometry,
( 0,3) is (X1,Y1)
(4,0) is (X2,Y2)
(7,4) is ( X3,Y3)
You need to remember the formula..
do let me know if u are still in doubt
( 0,3) is (X1,Y1)
(4,0) is (X2,Y2)
(7,4) is ( X3,Y3)
You need to remember the formula..
do let me know if u are still in doubt
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Another way.
The are of the triangle we want is in a rectangle with is 7 length and 4 wide (so this rectangle has an area of 28).
Now let's subtract to this area the 3 right triangles.
Triangle OPQ: (4*3)/2=6
2nd triangle: (1*7)/2=3,5
3rd triangle: (3*4)/2=6
The sum of the area of these 3 triangles is 15,5
We subtract it to the area of the rectangle and we have the area of PQR:
28-15,5=12,5
The are of the triangle we want is in a rectangle with is 7 length and 4 wide (so this rectangle has an area of 28).
Now let's subtract to this area the 3 right triangles.
Triangle OPQ: (4*3)/2=6
2nd triangle: (1*7)/2=3,5
3rd triangle: (3*4)/2=6
The sum of the area of these 3 triangles is 15,5
We subtract it to the area of the rectangle and we have the area of PQR:
28-15,5=12,5
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sorrie its a typo....
1/2 mod( ( X1-X2)* (Y2-Y3) - (Y1-Y2)( X2-X3))
thanks for pointing out...
sorry Zag abt it ...
1/2 mod( ( X1-X2)* (Y2-Y3) - (Y1-Y2)( X2-X3))
thanks for pointing out...
sorry Zag abt it ...
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