Simplify 5x(x+3)-2(x^2+3x-4)

$5 x (x + 3) - 2 (x^{2} + 3 x - 4)$

Step 1

Simplify each term.

Apply the distributive property.

$5 x \cdot x + 5 x \cdot 3 - 2 (x^{2} + 3 x - 4)$

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

Move $x$ .

$5 (x \cdot x) + 5 x \cdot 3 - 2 (x^{2} + 3 x - 4)$

Multiply $x$ by $x$ .

$5 x^{2} + 5 x \cdot 3 - 2 (x^{2} + 3 x - 4)$

Multiply $3$ by $5$ .

$5 x^{2} + 15 x - 2 (x^{2} + 3 x - 4)$

Apply the distributive property.

$5 x^{2} + 15 x - 2 x^{2} - 2 (3 x) - 2 \cdot - 4$

Simplify.

Multiply $3$ by $- 2$ .

$5 x^{2} + 15 x - 2 x^{2} - 6 x - 2 \cdot - 4$

Multiply $- 2$ by $- 4$ .

$5 x^{2} + 15 x - 2 x^{2} - 6 x + 8$

Step 2

Simplify by adding terms.

Subtract $2 x^{2}$ from $5 x^{2}$ .

$3 x^{2} + 15 x - 6 x + 8$

Subtract $6 x$ from $15 x$ .

$3 x^{2} + 9 x + 8$