hello!
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In order to simplify this expression, we need to combine like terms:-
![\longrightarrow\sf{6e+10e-9}](https://img.qammunity.org/2022/formulas/mathematics/college/lhobdtnc8gmntu7r8xtkedixnpq8hp10hi.png)
Add the e's:-
![\longrightarrow\sf{16e-9}](https://img.qammunity.org/2022/formulas/mathematics/college/rjq6n4fjnez7wyfs5eg7dxyo673saz1g0f.png)
Are there any more like terms? No, because 16e and -9 aren't like terms.
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note:-
Hope everything is clear; if you need any clarification/explanation, kindly let me know, and I will comment and/or edit my answer :)