Simplify (9x-5)(9x+5)

$(9 x - 5) (9 x + 5)$

Step 1

Expand $(9 x - 5) (9 x + 5)$ using the FOIL Method.

Apply the distributive property.

$9 x (9 x + 5) - 5 (9 x + 5)$

Apply the distributive property.

$9 x (9 x) + 9 x \cdot 5 - 5 (9 x + 5)$

Apply the distributive property.

$9 x (9 x) + 9 x \cdot 5 - 5 (9 x) - 5 \cdot 5$

Step 2

Simplify terms.

Combine the opposite terms in $9 x (9 x) + 9 x \cdot 5 - 5 (9 x) - 5 \cdot 5$ .

Reorder the factors in the terms $9 x \cdot 5$ and $- 5 (9 x)$ .

$9 x (9 x) + 5 \cdot 9 x - 5 \cdot 9 x - 5 \cdot 5$

Subtract $5 \cdot 9 x$ from $5 \cdot 9 x$ .

$9 x (9 x) + 0 - 5 \cdot 5$

Add $9 x (9 x)$ and $0$ .

$9 x (9 x) - 5 \cdot 5$

Simplify each term.

Rewrite using the commutative property of multiplication.

$9 \cdot 9 x \cdot x - 5 \cdot 5$

Multiply $x$ by $x$ by adding the exponents.

Move $x$ .

$9 \cdot 9 (x \cdot x) - 5 \cdot 5$

Multiply $x$ by $x$ .

$9 \cdot 9 x^{2} - 5 \cdot 5$

Multiply $9$ by $9$ .

$81 x^{2} - 5 \cdot 5$

Multiply $- 5$ by $5$ .

$81 x^{2} - 25$