# 2x + 5 = 47variable equations

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The key to answering this kind of question is that you want to do whatever is necessary to get the unknown -- the letter -- by itself on one side of the equals sign.

2x + 5 = 47

First you want to get rid of the 5. Subtract 5 from **both sides** of the equation:

2x + 5

- 5= 47- 52x = 42

Now you need to get rid of the 2. You can divide both sides by 2:

2x

/2= 42/2x = 21

Hi!! I always tell my students to pretend that we are playing a game of undo what the teacher has done in order to solve equations.

For example, in the first one you are **multiplying** the 2 and x and **adding** the 5. To undo those operations you do the opposites. Multiplying and dividing undo each other while adding and subtracting undo each other. So to undo this problem we will **subtract **the 5 and **divide **the 2. Here's how to do it step by step.

2x +5 = 47 (We always undo the number with **no** letter FIRST!)

2x +5 **-5** = 47 **-5 **(Subtract the 5 to undo the adding.)

2x = 42 (-5 +5 equals 0)

Now divide by 2 to undo multiplication.

2x**/2** = 42**/2**

x = 21

x=21

2X+5=47 here are the rules to solving

Rule 1: look at the question

Rule 2: how many terms [in this case it is three]

Rule 3:Do the opposite operation of the number by 2X [the term you are solving for]. transfer the number to over the = sign

Rule 4: After the opposite operation divide the answer you got using the opposite operation with the variable you are solving for. so it is like this: 2X+5=47

opposite operation: 2x=47-5

2X=42

in order to let the x by itself divide the number by it

**so 42 divided by 2 is 21.**

2x + 5 = 47

combine the like terms by minusing 5 on each side.

2x + 5 = 47

- 5 - 5

2x = 42

now divide by 2 to get x by itself

`(2x)/2 = 42/2 `

**x= 21**

We want to solve for x given:

2x + 5 = 47

First, we undo any addition or subtraction: Since five is being added, we will subtract.

2x = 42

Then we undo any multiplication or division: Since two is being multiplied, we will divide.

x = 21

2x + 5 = 47

To solve this equation first subtract 5 from both sides

By subtracting 5 from both sides your equation should look like

**2x = 42** now divide both sides from 2

By dividing both sides from 2 your equation should look like

**x = 21 **which is your answer

**Equation:**

2x+5=47

2x+[5-5]=47-5

2x=42

2x/2=42/2

x=21

Isolate the variable first

2x + 5 = 47

Now move 5 to the other side

2x=47-5

2x=42

Now divide x by 2 to get x

**x=21**

2x + 5 = 47

The key finding this is to isolate x, which is unknown,

2x+5-5=47-5 (subtracting 5 on both sides)

2x=42

2x/2=42/2 (dividing both sides by 2)

**x=21 Answer.**

2x+5=47

2x=47-5

2x=42

X=42/2

X= 21