Final answer:
To simplify the expression 3^4 x 5^4, we use the rule that when multiplying two terms with the same base, we add their exponents. The simplified expression is 50625.
Step-by-step explanation:
To simplify the expression 3^4 x 5^4 so it only has one exponent, we use the rule that when multiplying two terms with the same base, we add their exponents. So we have:
3^4 x 5^4 = (3 x 3 x 3 x 3) x (5 x 5 x 5 x 5) = 81 x 625 = 50625.
Therefore, the simplified expression is 50625.