The notation ##(a,b,c)produces a number that is a less than the product of b and c raised to the a power. When ##(2,5,x)=23, what is the value of x?

a. 0
b. 1/2
c. 1
d. 2
e. 5

please answer and explain

Things are a bit murky, but

2*5^x - x = 23
(2*5)^x - x = 23
are both tough to solve

Now, 5^2 - 2 = 23, but that doesn't fit the alleged formula. I suspect a typo