We want to find x right, so everything that does not have x you can move to the other side. 5x=-5-65-65. So that should be your equation so far. Now we know that when there are two negatives it is a negative and you add so -5-65=-70-65=-135. So your equation now should be: 5x=-135. Now we can divide -135 with 5 which gives us... -27! There’s your answer. Hope this was correct!
is the mass (in mg) remaining after 
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