5хх²-7х×4х²+0,5×2хх³+8-х= 3ав²-8х+4в²а+5ва×3в=

Let's solve the provided equations step-by-step.

Equation 1:

\(5xx² - 7x \times 4x² + 0.5 \times 2xx³ + 8 - x = 0\)

Let's simplify each term:

1. \(5xx²\) = \(5x^3\)
2. \(-7x \times 4x²\) = \(-28x^3\)
3. \(0.5 \times 2xx³\) = \(x^4\)
4. Combine the constant and the linear term: \(8 - x\).

Now substitute these back into the equation:

\[ 5x^3 - 28x^3 + x^4 + 8 - x = 0 \]

Combine like terms for \(x^3\):

\[ x^4 - 23x^3 - x + 8 = 0 \]

Equation 2:

\(3ab² - 8x + 4b²a + 5ba \times 3b = 0\)

Again, we'll simplify each term:

1. \(3ab²\) remains \(3ab²\)
2. \(-8x\) remains as is
3. \(4b²a\) remains as is
4. \(5ba \times 3b\) = \(15ab²\)

Now substitute these back into the equation:

\[ 3ab² - 8x + 4b²a + 15ab² = 0 \]

Combine like terms for \(ab²\):

\[ (3ab² + 15ab²) - 8x + 4b²a = 0 \]

This simplifies to:

\[ 18ab² - 8x + 4b²a = 0 \]

Summary of Equations

Now we have simplified to:

1. \(x^4 - 23x^3 - x + 8 = 0\)
2. \(18ab² + 4b²a - 8x = 0\)

If you need further help with solutions or specific methods to solve these equations, let me know!