The number is = 10x+y
if reverse the digits, the number is: 10y+x
The sum fo its digits is = x+y=5
I suggest this system of equations:
(10y+x)-(10x+y)=27 ⇒9y-9x=27
x+y=5
We can solve this system of equations by equaliztion method
x=5-y
9y-9(5-y)=27
9y-45+9y=27
18y=27+45
18y=72
y=72/18
y=4
x=5-y
x=5-4=1
The number is: 10x+y=10(1)+4=14
Answer: the number is 14
The equation seems to be
1
-------- = 5 ^ (x + 4)
25
In that case, this is the solution, stept by step:
1) factor 25: 25 = 5^2
1
=> ----------- = 5^(x + 4)
5^2
2) invert 5^2
=> 5^(-2) = 5^(x+4)
3) Given that the bases are equal, the exponents also have to be equal:
=> - 2 = x + 4
3) transpose +4:
=> - 2 - 4 = x
=> x = - 6
Answer: - 6
