If the area of the parallelogram with a and b as two adjacent sides is 15 sq. units, then the area of the parallelogram having 3a+2b and a+3b as two adjacent sides in sq. units is

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Accepted Answer

Correct answer: B. (b) : Area of parallelogram with adjacent sides a and b is |a b |. ⇒ |a b |=15 sq. units Area of parallelogram with sides (3a+2b ) and (a+3b ) is | (3a+2b ) (a+3b ) | = |3 (a a )+9 (a b )+2 (b a )+6 (b b ) | = |9 (a b )-2 (a b ) |=7 |a b | =7 15 sq. units =105 sq. units.

$If the area of the parallelogram with a and b as two adjacent sides is 15 sq. units, then the area of the parallelogram having 3 a + 2 b and a + 3 b as two adjacent sides in sq. units is$

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