Simplify (5-7x)(5+7x)

$(5 - 7 x) (5 + 7 x)$

Step 1

Expand $(5 - 7 x) (5 + 7 x)$ using the FOIL Method.

Apply the distributive property.

$5 (5 + 7 x) - 7 x (5 + 7 x)$

Apply the distributive property.

$5 \cdot 5 + 5 (7 x) - 7 x (5 + 7 x)$

Apply the distributive property.

$5 \cdot 5 + 5 (7 x) - 7 x \cdot 5 - 7 x (7 x)$

Step 2

Simplify and combine like terms.

Simplify each term.

Multiply $5$ by $5$ .

$25 + 5 (7 x) - 7 x \cdot 5 - 7 x (7 x)$

Multiply $7$ by $5$ .

$25 + 35 x - 7 x \cdot 5 - 7 x (7 x)$

Multiply $5$ by $- 7$ .

$25 + 35 x - 35 x - 7 x (7 x)$

Rewrite using the commutative property of multiplication.

$25 + 35 x - 35 x - 7 \cdot 7 x \cdot x$

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

Move $x$ .

$25 + 35 x - 35 x - 7 \cdot 7 (x \cdot x)$

Multiply $x$ by $x$ .

$25 + 35 x - 35 x - 7 \cdot 7 x^{2}$

Multiply $- 7$ by $7$ .

$25 + 35 x - 35 x - 49 x^{2}$

Subtract $35 x$ from $35 x$ .

$25 + 0 - 49 x^{2}$

Add $25$ and $0$ .

$25 - 49 x^{2}$