Question

The factorised form of $21x^2{y}^3+27x^3{y}^3$ is __________.

• A. $3x^2{y}^3(7+9x)$
• B. $3x^2{y}^2(7y+9x)$
• C. $7xy+9x^{2}y$
• D. $7\times 3\times 4(x+y)$

Answer 1

The correct option is A $3x^2{y}^3(7+9x)$

$21x^2{y}^3+27x^3{y}^3$
$=3\times 7\times x\times x\times y\times y\times y+3\times 3\times 3\times x\times x\times x\times y\times y\times y$
$=3\times x\times x\times y\times y\times y(7+9x)$
$=3x^2{y}^3(7+9x)$