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Can someone check if i did this correct. it’s number 4 if you’re wondering.

Prove the divisibility of the following numbers: 25^9 + 5^7 is divisible by 30.also, read as (25 to the power of 9) + (5 to the power of 7) is divisible by 30. blank x 30what is the blank? ( it should be expressed in exponent form)

What is the solution to the equation below? 3/x-2+6=square root x-2 +8