(y-7) ² - 4(y-7) -45

To simplify the given expression, let's expand and simplify each term step by step:

Step 1: Expand the squared term. (y - 7)² = (y - 7) * (y - 7) = y * y - 7 * y - 7 * y + 7 * 7 = y² - 14y + 49

Step 2: Distribute the -4 to the terms inside the parentheses. -4(y - 7) = -4y + 28

Now, let's substitute the expanded terms into the original expression and simplify further:

(y - 7)² - 4(y - 7) - 45 = (y² - 14y + 49) - 4y + 28 - 45 = y² - 14y + 49 - 4y + 28 - 45 = y² - 14y - 4y + 49 + 28 - 45 = y² - 18y + 32

So, the simplified form of (y - 7)² - 4(y - 7) - 45 is y² - 18y + 32.