hello!
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In order to simplify this expression, we need to use the distributive property, which states:-
![\bigstar{\underline{\boxed{\pmb{a(b+c)=ab+ac}}}\longleftarrow\sf{the~distributive~property}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ai56apqa6rim35i0xjzkzfvk1g9sez78fk.png)
Where:-
we distribute a by multiplying it times b and c
Now, let's use this property to simplify our expression:-
![\longrightarrow\sf{-6(10+9v)}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8huvvx87moxqj2l0r3ppnf9sk96i25db10.png)
![\longrightarrow\sf{-60-54v}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/hkf089otcbgo96zj3cqg9w8dhrdi90fwug.png)
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note:-
Hope everything is clear; if you need any clarification/explanation, kindly let me know, and I'll comment and/or edit my answer :)