Answer: 5^7
Step-by-step explanation: When multiplying exponents with the same base number you add the exponents together. For example 2^4 x 2^3 will multiply to a product of 2^7.
Use the distributive property to multiply y by -6y^3 and -8. This gives you -6y^4 - 8y + y^4. Add the like terms and you get -5y^4 - 8y.
Therefore, the simplest form of this expression is -5y^4 - 8y.
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