Answer:
[tex](x-9)^2-87[/tex]
Step-by-step explanation:
(x - 9)² = 87
Move the -6 to the other side
x² - 18x = 6
The number you add to each side is (b/2)²
(b/2)² is (-18/2)² = 81
x² - 18x + 81 = 87
