Rewrite the equation as .

Subtract from both sides of the equation.

Divide each term in by .

Cancel the common factor of .

Cancel the common factor.

Divide by .

Move the negative in front of the fraction.

Take the natural logarithm of both sides of the equation to remove the variable from the exponent.

Expand by moving outside the logarithm.

The natural logarithm of is .

Multiply by .

Divide each term in by .

Simplify .

Dividing two negative values results in a positive value.

Cancel the common factor of .

Cancel the common factor.

Divide by .

Move the negative in front of the fraction.

Solve for t H=a+be^(-kt)