Question

(5m-3)(5m+3)+(9-m)(m+9)​

Answer 1

Ответ:

$=25m^2-9+(9-m)(9+m)=25m^2-9+81-m^2=24m^2+72.$

Объяснение:

формула

$(a-b)(a+b)=a^2-b^2.$

Answer 2

Ответ:

(25m²-9)+(81-m²)=24m²-72

Answer 3

To simplify the expression (5m-3)(5m+3) + (9-m)(m+9), you can use the distributive property to expand both terms and then combine like terms:

(5m-3)(5m+3) + (9-m)(m+9)

Let's simplify each term step by step:

1. Expand the first term (5m-3)(5m+3):

(5m-3)(5m+3) = 5m(5m) + 5m(3) - 3(5m) - 3(3) = 25m^2 + 15m - 15m - 9

Notice that the middle terms (15m and -15m) cancel each other out.

So, (5m-3)(5m+3) simplifies to 25m^2 - 9.

2. Expand the second term (9-m)(m+9):

(9-m)(m+9) = 9(m) + 9(9) - m(m) - m(9) = 9m + 81 - m^2 - 9m

Now, combine like terms:

9m - 9m cancels out.

So, (9-m)(m+9) simplifies to 81 - m^2.

Now, you can add the simplified terms together:

25m^2 - 9 + 81 - m^2

Combine like terms:

(25m^2 - m^2) + (-9 + 81)

24m^2 + 72

So, the simplified expression is 24m^2 + 72.