Simplify (2j+7)(2j-7)

$(2 j + 7) (2 j - 7)$

Step 1

Expand $(2 j + 7) (2 j - 7)$ using the FOIL Method.

Apply the distributive property.

$2 j (2 j - 7) + 7 (2 j - 7)$

Apply the distributive property.

$2 j (2 j) + 2 j \cdot - 7 + 7 (2 j - 7)$

Apply the distributive property.

$2 j (2 j) + 2 j \cdot - 7 + 7 (2 j) + 7 \cdot - 7$

Step 2

Simplify and combine like terms.

Simplify each term.

Rewrite using the commutative property of multiplication.

$2 \cdot 2 j \cdot j + 2 j \cdot - 7 + 7 (2 j) + 7 \cdot - 7$

Multiply $j$ by $j$ by adding the exponents.

Move $j$ .

$2 \cdot 2 (j \cdot j) + 2 j \cdot - 7 + 7 (2 j) + 7 \cdot - 7$

Multiply $j$ by $j$ .

$2 \cdot 2 j^{2} + 2 j \cdot - 7 + 7 (2 j) + 7 \cdot - 7$

Multiply $2$ by $2$ .

$4 j^{2} + 2 j \cdot - 7 + 7 (2 j) + 7 \cdot - 7$

Multiply $- 7$ by $2$ .

$4 j^{2} - 14 j + 7 (2 j) + 7 \cdot - 7$

Multiply $2$ by $7$ .

$4 j^{2} - 14 j + 14 j + 7 \cdot - 7$

Multiply $7$ by $- 7$ .

$4 j^{2} - 14 j + 14 j - 49$

Add $- 14 j$ and $14 j$ .

$4 j^{2} + 0 - 49$

Add $4 j^{2}$ and $0$ .

$4 j^{2} - 49$