Find a,b,c (x-3)(x+4)=0

$(x - 3) (x + 4) = 0$

Simplify the left side.

Simplify $(x - 3) (x + 4)$ .

Expand $(x - 3) (x + 4)$ using the FOIL Method.

Apply the distributive property.

$x (x + 4) - 3 (x + 4) = 0$

Apply the distributive property.

$x \cdot x + x \cdot 4 - 3 (x + 4) = 0$

Apply the distributive property.

$x \cdot x + x \cdot 4 - 3 x - 3 \cdot 4 = 0$

Simplify and combine like terms.

Simplify each term.

Multiply $x$ by $x$ .

$x^{2} + x \cdot 4 - 3 x - 3 \cdot 4 = 0$

Move $4$ to the left of $x$ .

$x^{2} + 4 \cdot x - 3 x - 3 \cdot 4 = 0$

Multiply $- 3$ by $4$ .

$x^{2} + 4 x - 3 x - 12 = 0$

Subtract $3 x$ from $4 x$ .

$x^{2} + x - 12 = 0$

Once the quadratic is in standard form, the values of $a$ , $b$ , and $c$ can be found.

$a x^{2} + b x + c$

Use the standard form of the equation to find $a$ , $b$ , and $c$ for this quadratic.

$a = 1$ , $b = 1$ , $c = - 12$