|
Question 29678: (3x+2y)(2y+3x)
Answer by sdmmadam@yahoo.com(530)   (Show Source):
You can put this solution on YOUR website! (3x+2y)(2y+3x)
=(3x+2y)(3x+2y) (applying additive commutativity in the second bracket which is nothing but swapping the terms 2y and 3x)
=(3x+2y)^2
=(3x)^2+2(3x)(2y)+(2y)^2 [using (a+b)^2=a^2+2ab+b^2 where here a = 3x and b=2y]
=9x^2+12xy+4y^2
Note: You may directly multiply using bracket expansion as follows:
(3x+2y)(2y+3x)
=3x(2y+3x) + 2y(2y+3x) {first term of the first bracket multiplied by the whole of the next bracket plus second term of the first bracket multiplied by the whole of the next bracket)
=[3xX(2y)+3xX(3x)] + [2yX(2y)+2yX(3x)]
=(6xy+9x^2)+(4y^2+6xy)
=9x^2+12xy+4y^2 (grouping like terms which is nothing but using additive commutativity and associativity repeatedly )
Answer:(3x+2y)(2y+3x)=9x^2+12xy+4y^2
|
|
|
| |
