expand (x-3)(x+3) — step-by-step solution

⚠ (x-3)(x+3) is read as (x-3)*(x+3): use (...)*(...) for multiplication, use (...)^(...) for a power

Let's write in expanded form:

(x - 3) \cdot (x + 3)

ⓘ Expand by multiplying each term inside the parentheses:

(x - 3) \cdot (x + 3)

x \cdot x

+ x \cdot 3

- 3 x

- 3 \cdot 3

x \cdot x

+ x \cdot 3

- 3 x

- 3 \cdot 3

ⓘ Multiplying powers with the same base adds the exponents:

x \cdot x

x^{2}

■Like terms are grouped by adding their coefficients:

x \cdot 3 - 3 x

0

■Multiplications are done before additions and subtractions:

3 \cdot 3

9

x^{2} + 0 - 9

ⓘ Adding 0 changes nothing:

0 - 9

-9

▶Expanded form:

x^{2} - 9