If area of the parallelogram with a and b as two adjacent sides is 20 square units, then the area of the parallelogram having 3 a + b and 2 a +3 b as two adjacent sides in square units is

Step-by-step solution

We have | a b |=20 and we have to find value of aligned & |(3 a + b ) (2 a +3 b )| & (3 a + b ) (2 a +3 b ) & =6( a b )+9( a b )+2( b a )+3( b b ) & =0+9( a b )-2( a b )+0=7( a b ) aligned Hence area of the required parallelogram =7 20=140