Answer
Fill the blanks with
... 4 ... 1 ... 20
Work Step by Step
$9(x^{2}-8x+4-4)=9(x-2)^{2}-36$
(adding 4 to the first parentheses completes the square)
$-16(y^{2}+2y+1-1)=-16(y-1)^{2}+16$
(adding 1 to the second parentheses completes the square)
So,
LHS= $9(x-2)^{2}-16(y-1)^{2}-20$
To move the $(-20)$ to the other side, we add 20 to both sides.
Fill the blanks with
... 4 ... 1 ... 20
