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Solve the equation: x+9 = 18-2x.

User Iksnae
by
6.9k points

2 Answers

1 vote

Step-by-step explanation:

to solve for a variable means to transform the equation so that we get

x = ...

or

... = x

always remember : when transforming an equation we apply every change in the same way to both sides. otherwise we would destroy the information of the original equation.

starting with

x + 9 = 18 - 2x

we can e.g. add 2x to both sides

x + 2x + 9 = 18

3x + 9 = 18

then we can subtract 9 from both sides

3x = 18 - 9 = 9

then we can divide both sides by 3

x = 3

done.

User Matt Moore
by
7.7k points
5 votes

Final answer:

To solve the equation x + 9 = 18 - 2x, we first add 2x to both sides, then subtract 9 from both sides, and finally divide by 3 to get that x equals 3.

Step-by-step explanation:

To solve the equation x + 9 = 18 - 2x, you want to find the value of x that makes both sides of the equation equal. Here is a step-by-step process:

  1. First, you need to gather all the x terms on one side and the constants on the other side. You can do this by adding 2x to both sides of the equation, which gives you 3x + 9 = 18.
  2. The next step is to isolate the variable x by getting rid of the constant 9 on the left-hand side. You can do this by subtracting 9 from both sides of the equation, leading to 3x = 9.
  3. Finally, divide both sides by 3 to solve for x, which results in x = 3.

So, the solution to the equation x + 9 = 18 - 2x is x = 3.

User Woninana
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7.2k points