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Help please !!! I don’t know what to do

Help please !!! I don’t know what to do-example-1
User Harmv
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1 Answer

8 votes
8 votes

9514 1404 393

Answer:

6. x = 3

8. x = -7.5

Explanation:

Put the number in place of the expression it is equal to, then solve for x.

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6) g(x) = -x +5

2 = -x +5 . . . . . . . . . g(x) is replaced by 2, because g(x) = 2

x +2 = 5 . . . . . . . . . . add x to both sides

x = 3 . . . . . . . . . . . . . subtract 2 from both sides

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8) n(x) = -2x -21

-6 = -2x -21 . . . . . n(x) is replaced by its equal: -6

3 = x +10.5 . . . . . . divide both sides by -2

-7.5 = x . . . . . . . . . subtract 10.5 from both sides

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Additional comment

We have shown a couple of ways these equations can be solved. You can separate the x-term and the constant terms before you divide by the x-coefficient, or you can do it after. In the first equation, we could have solved it ...

2 -x +5

-3 = -x . . . . subtract 5

3 = x . . . . . . multiply by -1

The way we did it avoids negative numbers.

User Martin Monperrus
by
2.9k points