4,2x+8=8-7x

To solve the equation \( 4.2x + 8 = 8 - 7x \), follow these steps:

1. Simplify both sides of the equation.

Since the \(8\) on both sides cancels each other out, we can eliminate it:

\[ 4.2x + 8 - 8 = 8 - 7x - 8 \]

This simplifies to:

\[ 4.2x = -7x \]

2. Next, we want to get all terms involving \(x\) on one side. We can add \(7x\) to both sides:

\[ 4.2x + 7x = 0 \]

This simplifies to:

\[ 11.2x = 0 \]

3. Finally, divide both sides by \(11.2\):

\[ x = 0 \]

Thus, the solution to the equation \( 4.2x + 8 = 8 - 7x \) is

\[ \boxed{0} \]