How to mathematically deal with unexpected negative value

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For planck’s photon energy equation when calculating wavelength it makes no sense for it to be negative.

The answer I get is negative because the energy value is the only negative variable, heat is given out so it’s said that the reaction is exothermic heat taken in is positive.

Units:

$h=6.262\cdot 10^{-34}\ j\cdot s^{-1}$

$c=2.998\cdot 10^{8}\ m\cdot s^{—1}$

${NA}=6.022\cdot 10^{23}\ mol^{-1}$

$E=-533000\ j\cdot mol^{-1}$

$\lambda=x\cdot m$

$$ \lambda=\frac{h\cdot c\cdot {NA}}{E}=\frac{h\cdot c}{E} $$

$$ \lambda=\frac{(6.626\cdot 10^{-34})(2.998\cdot 10^{8})(6.022\cdot10^{23})}{(-533000)}=-224nm $$

Obviously the length can’t be negative so I just so I just put it as positive, but is there a mathematical technique for situations like this? I’m just trying to learn.

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Just make one of the other values negative as well, for example, let $c=-2.998\cdot 10^{8}\ m\cdot s^{—1}$. Then you get a positive length.