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प्रश्न
Trapezium given below; find its area.
उत्तर
For the triangle EBC,
S = 19 cm
Area of ΔEBC = `sqrt( 19 xx ( 19 - 16 ) xx ( 19 - 12 ) xx ( 19 - 10 ))`
= `sqrt( 19 xx 3 xx 7 xx 9 )`
= 59.9 sq.cm
Let h be the height.
Area of ΔEBC= `1/2` x 12 x h
⇒ 59.9 = 6h
⇒ h = `59.9/6` = 9.98 cm
Area of ABCD = `1/2` x ( 20 + 32 ) x 9.98
= `1/2` x 52 x 9.98
= 259.48 cm2
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