I need help pls help

$(5)(5^4)(x^3)(x^8)$

5^4 multiplied by 5 is the same as 5^5.

$(5^5)(x^3)(x^8)$

When two same variables with exponents are multiplied, the exponents add together.

$(5^5)({x}^{11})$

Expand the 5^5.

$(5*5*5*5*5)({x}^{11})\Rightarrow (3125)(x^{11})$

So your answer is:

$3,125x^{11}$