Question

how do remind the area of triangle by the formula of co-ordinate geometry??please reply please give me a way to remind it I forgot it overtime...

Answer 1

Its like write 1/2 | and write x (y-y) +x(y-y) +x (y-y) and ther write
1(2-3) +2(3-1)+3(1-2)

these 1,2&3 indicates about x1 , x2,x 3 and y1 , y2 ,y3

Answer 2

Hello...

The formula of area of triangle is.........

1/2[X1(Y2-Y3)+X2(Y3-Y1) +X3(Y1-Y2)]
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To memorize this formula is very easy.....
Usually students forget this formula because this seams to be very big
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But I have a idea that will make this this formula so easy to memorize......
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First u can observe that with X1. (Y2-Y3) is multiplied (here observe the numerical digit)
1 then 2 then 3 comes....
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In second term
X2(Y3-Y1)
digit 2 then 3 then come back to 1 in a cycle.....
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In third term.....
X3(Y1-Y2)
DIGIT 3 then come back to one then 2 in a cycle.....
.
.
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Hope......
Any doubt tell me