D(7,9) , E(1,1) and F(-1,-7) are the vertices of the triangle DEF . L(4,5) , M(-1,-3) , and N(2,1) are the mid points of DE , EF and FD respectively . prove that

area of triangle DEF/ area of triangle LMN =4/1


Area of ΔDEF=127×1+1×-7+-1×9-9×1+1×-1+-7×7                          =127-7-9-9-1-49                          =12-9+41                          =8And,Area of ΔLMN=124×-3+-1×1+2×5-5×-1+-3×2+1×4                          =12-12-1+10--5-6+4                          =12-3+7                          =2Thus,Area of ΔDEFArea of ΔLMN=82=41Hence proved.

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