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Answer:
k=10x+6
Step-by-step explanation:
64 is equal to 2^6, so we just have 2^6*4^5k
4^5x is equal to 2^10x and we have 2^6*2^10x=2^k
Apply exponent multiplication rule : a^m*a^n=a^m+n
We get 2^10x+6, so 10x+6 is our answer