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3 years ago

-3x + 9 = -18 what's the answer

Mathematics

2 answers:

Rudik [331]3 years ago

7 0

Answer:

x=9

Step-by-step explanation:

Hi there!

We are given the following equation:

-3x + 9 = -18

We want to solve for x

To do that, we need to isolate x on one side; the value of x (the answer) will be on the other side.

We can manipulate numbers in order to help us isolate x on one side.

First, let's remove 9 from the left side; subtract 9 from both sides

-3x + 9 = -18

- 9 -9

___________________

-3x = -27

Now, there are no more numbers on the left side, but we aren't done yet. The value of x is also equal to the value of 1x.

In order to find the value of 1x, we can divide both sides by -3, as if you divide any number by itself, the result is 1. x doesn't get divided (there are no other numbers or variables to divide x by when we divide -3x by -3), so the result on the left side would be 1x, or x.

Therefore, we need to divide both sides by -3

-3x/-3 = -27/-3

x= 9

(the number is not negative because when you divide a negative by a negative, the resulting number is positive)

Hope this helps!

Art [367]3 years ago

6 0

Answer:

x=9

Step-by-step explanation:

subtract 9 from both sides.

-3x = -27

divide by -3

x=9

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Step-by-step explanation:

You need to know:

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Divide -2 by 2 and then square it.

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Now we have

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Next add -5 - 1 = -6

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4 years ago

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Step-by-step explanation:

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2 years ago

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3 years ago

Marcos reads 3, books in 1 3/4 weeks.

Fofino [41]

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Step-by-step explanation:

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3 years ago

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IgorLugansk [536]

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Step-by-step explanation:

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3 years ago