-7x-1(10-x)=-58

Using the the distributive property equation

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 - This is another way of saying multiply each side by -1.

 - Since we have 2 negatives next to each other, one must be turned into a positive, in this case it's the x.

 - Combine them because you can only have one variable (x) in the end.

 - We do this to get rid of not only the 10 but the other numbers as well, and the only way to do so it to cancel them out.

 - We do this to get x alone with one number left over, and the only way to do so is to cancel everything out by dividing.

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the mean and mad

step-by-step explanation:

a is 8.b is 10.c is 10.5. d is -.5

step-by-step explanation:

just minus the smallest number from the biggest.