Simplify (a-11)(a+11)

$(a - 11) (a + 11)$

Step 1

Expand $(a - 11) (a + 11)$ using the FOIL Method.

Apply the distributive property.

$a (a + 11) - 11 (a + 11)$

Apply the distributive property.

$a \cdot a + a \cdot 11 - 11 (a + 11)$

Apply the distributive property.

$a \cdot a + a \cdot 11 - 11 a - 11 \cdot 11$

Step 2

Simplify terms.

Combine the opposite terms in $a \cdot a + a \cdot 11 - 11 a - 11 \cdot 11$ .

Reorder the factors in the terms $a \cdot 11$ and $- 11 a$ .

$a \cdot a + 11 a - 11 a - 11 \cdot 11$

Subtract $11 a$ from $11 a$ .

$a \cdot a + 0 - 11 \cdot 11$

Add $a \cdot a$ and $0$ .

$a \cdot a - 11 \cdot 11$

Simplify each term.

Multiply $a$ by $a$ .

$a^{2} - 11 \cdot 11$

Multiply $- 11$ by $11$ .

$a^{2} - 121$