Use the distributive property to simplify each expression.

-8\left(x+4\right)

-8(x+4) can be simplified using the distributive property as follows:

-8(x+4) = -8*x + (-8)*4

This simplifies to:

-8x - 32

Use the distributive property to simplify each expression.

12\ -\ \left(x+9\right)

To simplify the expression 12 - (x+9), we can apply the distributive property:

12 - (x+9) = 12 - x - 9

This simplifies to:

3 - x

Use the distributive property to simplify each expression.

2\left(5x-6\right)

To simplify the expression 2(5x-6), we can use the distributive property:

2(5x-6) = 2*5x - 2*6

This simplifies to:

10x - 12

Use the distributive property to simplify each expression.

3\left(4x+1\right)-10x

To simplify the expression 3(4x+1)-10x, we can use the distributive property:

3(4x+1)-10x = 3*4x + 3*1 - 10x

This simplifies to:

12x + 3 - 10x

Combining like terms, we have:

2x + 3