Solve $7/e^-x -4 =1$ ?

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Answer 1 · 2017-03-20T09:21:31

$x=ln(5/7) ~= -0.3365$
[If the equation is interpreted as: $7/e^-x -4 =1$ ]

Since the syntax in the original question the equation may be ambigious, I will define the equation as:

$7/e^-x -4 =1$

$7/e^-x = 5$

$7e^x = 5$

$e^x = 5/7$

$x = ln(5/7) ~= -0.3365$

Solve 7/e^-x -4 =17/e^-x -4 =1 ?