Respuesta :
Answer:
x = 5
Step-by-step explanation:
Notice that there is also a base 5 on the right hand side of the equation, therefore, let's move [tex]5^{x-4}[/tex] to the right by dividing both sides by it. and then re-writing the right hand side as 5 to a power:
[tex]2^{x-5}\,*\,5^{x-4}=5\\2^{x-5}=5/5^{x-4}\\2^{x-5}=5\,*\,5^{4-x}\\2^{x-5}=5^{5-x}[/tex]
Now apply log to both sides in order to lower the exponents (where the unknown resides):
[tex](x-5)\,log(2)=(5-x)\,log(5)[/tex]
Notice that when x = 5, this equation is true because it makes it the identity: 0 = 0
So, let's now examine what would be the solution of x is different from 5, and we can divide by (x - 5) both sides of the equation:
[tex]log(2)=\frac{5-x}{x-5} \,log(5)\\log(2)=-1\,\,log(5)\\log(2)=-log(5)[/tex]
which is an absurd because log(2) is [tex]\neq[/tex] from log(5)
Therefore our only solution is x=5
Answer:
if decimal no solution
if multiply x =5
Step-by-step explanation:
If this is a decimal point
2^(x-5) . 5^(x-4) = 5
Rewriting .5 as 2 ^-1
2^(x-5) 2 ^ -1 ^(x-4) = 5
We know that a^ b^c = a^( b*c)
2^(x-5) 2 ^(-1*(x-4)) = 5
2^(x-5) 2 ^(-x+4) = 5
We know a^ b * a^ c = a^ ( b+c)
2^(x-5 +-x+4) = 5
2^(-1) = 5
This is not true so there is no solution
If it is multiply
2^(x-5) * 5 ^(x-4) = 5
Divide each side by 5
2^(x-5) * 5 ^(x-4) * 5^-1 = 5/5
We know that a^ b * a^c = a^ ( b+c)
2^(x-5) * 5 ^(x-4 -1) = 1
2^(x-5) * 5 ^(x-5) = 1
The exponents are the same, so we can multiply the bases
a^b * c*b = (ac) ^b
(2*5) ^ (x-5) = 1
10^ (x-5) = 1
We know that 1 = 10^0
10^ (x-5) = 10 ^0
The bases are the same so the exponents are the same
x-5 = 0
x=5