SOLUTION: Could you please explain to me the process to solve the equations for x 1.3e^2x=28 2.2ln(x-5)=3.65

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Question 220562: Could you please explain to me the process to solve the equations for x
1.3e^2x=28
2.2ln(x-5)=3.65

Answer by jsmallt9(3759) About Me  (Show Source):
You can put this solution on YOUR website!
These problems require that we know how to convert from exponential form to logarithmic form and vice versa. So we we need to know:
  • log%28a%2C+b%29+=+c in exponential form is: a%5Ec+=+b
  • a%5Eb+=+c in logarithmic form is: log%28a%2C+c%29+=+b

We also need to understand that ln%28x%29 is the common name for log%28e%2C+%28x%29%29

Now we're ready to start:
1. 3e%5E%282x%29+=+28
Whenever we solve for x we are trying to isolate x on one side of the equation. So we'll start by dividing by 3:
e%5E%282x%29+=+28%2F3
Now we need to get x out of the exponent. This is where we need to know that this is the time to convert ro logarithmic form:
log%28e%2C+%2828%2F3%29%29+=+2x
ln%2828%2F3%29+=++2x
Now we can divide by 2:
%28ln%2828%2F3%29%29%2F2+=++x
With a calculator we san simplify the left side:
1.1167961107535471+=+x

2. 2ln%28x-5%29=3.65%0D%0ADivide+by+2%3A%0D%0A%7B%7B%7Bln%28%28x-5%29%29=+1.825
Now we need to get x out of the argument of the logarithm. This is the time to convert to exponential form:
e%5E1.825+=+x-5
Adding 5 to each side:
e%5E1.825+%2B+5+=+x
With a calculator we can simplify the left side:
11.2027950191048646+=+x