Question

(2a-5)²+(9-2a)(9+2a)

Answer 1

Ответ:

Объяснение:

=4а^2-20а+25+81-4а^2=

-20а+106

Answer 2

To simplify the expression (2a-5)² + (9-2a)(9+2a), you can use the distributive property and then combine like terms. Here are the steps:

1. Start by squaring the binomial (2a-5)²:

   (2a-5)² = (2a-5)(2a-5)

   Use the FOIL method to expand it:

   (2a-5)(2a-5) = 4a² - 10a - 10a + 25 = 4a² - 20a + 25

2. Next, multiply the two binomials (9-2a) and (9+2a):

   (9-2a)(9+2a) = 99 + 92a - 2a9 - 2a2a

   Use the distributive property:

   = 81 + 18a - 18a - 4a²

3. Now, you can add the two simplified expressions together:

   (4a² - 20a + 25) + (81 + 18a - 18a - 4a²)

4. Combine like terms:

   4a² - 4a² - 20a + 18a - 18a + 25 + 81

5. The 4a² and -4a² cancel each other out:

   -20a + 18a - 18a + 25 + 81

6. Combine the remaining like terms:

   -20a + 18a - 18a = -20a

7. The final simplified expression is:

   -20a + 25 + 81 = -20a + 106

So, (2a-5)² + (9-2a)(9+2a) simplifies to -20a + 106.