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ABCD is a parallelogram. X and Y are the midpoints of BC and CD. Find the ratio of ar (AAXY)to ar (llgm ABCD).22. |
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Answer» Given that ABCD ia a parallelogram. X and Y are the mid points of BC and CD Construction: Join BD Since X and Y are the mid points of sides BC and CD respectively, therefore in triangle BCD, XY//BD and XY=1/2 BD implies area of triangle CYX= 1/4 area of triangle DBC { In triangle BCD, if X is the mid point of BC and Y is the mid pt of CD then area triangle CYX=1/4 area triangle DBC} IMPLIES AREA TRIANGLE CYX= 1/8 parallelogram ABCD [Area parallelogram is twice the area of triangle made by the diagonal] Since parallelogram ABCD and triangle ABX are between same // lines AB and BC and BX=1/2BC Therefore, area triangle ABX= 1/4 area //gm ABCD Similarly, area triangle AYD= 1/4 area parallelogram ABCD Now, area triangle AXY= area/parallelogram ABCD- {ar triangleABX + ar AYD + ar CYX} = parallelogramABCD - {1/4 + 1/4 + 1/8} area of parallelogram =area of parallelogram- 5/8 area parallelogram ABCD =3/8 area /parallelogram ABCD. |
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