Question

Find the missing term in the following expressions to make each a perfect square.
$\square +18x+9$

Answer 1

Find the missing term

$\square +18x+9$

$\square +2\times 3\times 3x+9$

$\square +2\times 3\times 3x+(3{)}^2$

$\square +2\times 3\times 3x+(3{)}^2$

$A^2+2\times A\times B+B^2$

Now,

$A=3x$

$A^2=(3x{)}^2=9x^2$

$A^2+2AB+B^2$

$9x^2+18x+9$

Hence, missing term$=9x^2$

This is the answer.