Note:
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Solve for x in the following equation.
Problem 7.6d:
Answer:
Exact answer: Approximate answer:
Solution:
The first step is to isolate
Subtract .921 from both sides of the equation.
Divide both sides of the equation by .278.
The next step is to isolate the variable x.
Take the natural logarithm of both sides of the equation..
The exact answer is and the approximate answer is
Check the solution by substituting in
the original equation for x. If the left side of the equation equals the
right side of the equation after the substitution, you have found the
correct answer.
You can also check your answer by graphing the function (formed by
subtracting the right side of the original equation from the left side).
Look to see where the graph crosses the x-axis; that will be the real
solution. Note that the graph crosses the x-axis at -1.065824. This means
that -1.065824 is the real solution.
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