If `|x_1y_1 1x_2y_2 1x_3y_3 1|=|a_1b_1 1a_2b_2 1a_3b_3 1|` then the two triangles with vertices `(x_1, y_1),(x_2,y_2),(x_3,y_3)` and `(a_1,b_1),(a_2,b

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If `|x_1y_1 1x_2y_2 1x_3y_3 1|=|a_1b_1 1a_2b_2 1a_3b_3 1|` then the two triangles with vertices `(x_1, y_1),(x_2,y_2),(x_3,y_3)` and `(a_1,b_1),(a_2,b_2),(a_3,b_3)` are equal to area (b) similar congruent (d) none of these
A. equal in area
B. similar
C. congruent
D. none of these


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Salim Ahmed Kawsar

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Correct Answer - A
We have
`(1)/(2)|{:(x_1,,y_1,,1),(x_2,,y_2,,1),(x_3,,y_3,,1):}|=|{:(a_1,,b_1,,1),(a_2,,b_2,,1),(a_3,,b_3,,1):}|or (1)/(2)|{:(x_1,,y_1,,1),(x_2,,y_2,,1),(x_3,,y_3,,1):}|=(1)/(2)|{:(a_1,,b_1,,1),(a_2,,b_2,,1),(a_3,,b_3,,1):}|`
Hence, the area of triangle with vertices `(x_1,y_1),(x_2,y_2),(x_3,x_3)` is the same as the area of triangle with vertices `(a_1,b_1),(a_2,b_2),(a_3,b_3)`. Hence, the two triangles are equal in area.

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