Simplify (x^2-9)-(x^2-5x+6)

$(x^{2} - 9) - (x^{2} - 5 x + 6)$

Simplify each term.

Apply the distributive property.

$x^{2} - 9 - x^{2} - (- 5 x) - 1 \cdot 6$

Simplify.

Multiply $- 5$ by $- 1$ .

$x^{2} - 9 - x^{2} + 5 x - 1 \cdot 6$

Multiply $- 1$ by $6$ .

$x^{2} - 9 - x^{2} + 5 x - 6$

Simplify by adding terms.

Combine the opposite terms in $x^{2} - 9 - x^{2} + 5 x - 6$ .

Subtract $x^{2}$ from $x^{2}$ .

$0 - 9 + 5 x - 6$

Subtract $9$ from $0$ .

$- 9 + 5 x - 6$

Subtract $6$ from $- 9$ .

$5 x - 15$