How to solve an equation

Question

Solve 2x + 1 = 9

show all steps

Answer 1

To solve for

2x + 1 =9

The first step is to eliminate the number that is standing alone - the number that does not have x with it. In this case, it's the number 1. We are going to subtract both sides by number 1

2x+1 =9

-1 -1

By eliminating 1 on the left side, the number 1 will disappear. On the right side, number 9 is reduced by 1. 9 subtracts 1 equal 8

2x = 8

The next step is to find x. As we look into our equation, the number 2 is standing next to x. So, in order to get x alone, we will need to eliminate 2. We can do the elimination by dividing both sides by 2.

2x =8

÷2 =÷2

1x = 4

x = 4 (1 times x is just x)

Conclusion: x=4 is what we needed for the solution.

Answer 2

"Solve" for an algebra question like this means "get x by itself on one side of the equation."

There are two things in our way right now: a 2 that is multiplying the x and a 1 that is being added to the x. To get rid of them, we work through the order of operations BACKWARD. That means we'll worry about the number that's being added/subtracted before the number that's being multiplied/divided. (The order of operations is like building a house; isolating x is like tearing the house back down.)

First stop: get rid of that +1. To undo addition, we subtract (because they are opposites), and whatever we do to one side of the equation we must do to the other. Take a look:

2x + 1 = 9

-1 -1

2x + 0 = 8

Which is the same as just 2x = 8

Step two: get rid of the "times 2." To undo multiplication, we divide, and once again we do the same thing on the other side of the equation as well:

2x = 8

/2 /2

1x = 4

Which is the same as

x = 4

x is by itself on one side! Hooray, problem solved!

Answer 3

How to solve an equation

Solve 2x + 1 = 9

Step #1: Are there any same side like terms? No

Step #2: Subtract one from both sides

2x + 1 = 9

-1 -1

2x = 8 Step #3: Divide both sides by 2

2 2

x = 4 Check your answer.

2(4) + 1 =9

9=9

Your answer is correct.

Answer 4

Hello, thank you for taking the time to post your question!

When you are solving an expression like this you want to isolate the variable “x” … to do that here I would start by combining like terms

2x + 1 = 9

2x = 8

Then you can divide both sides by 2 to get the “x” term by itself

2x = 8

x = 4

so the solution to this equation is x = 4

I hope that helps get you moving in the right direction! Feel free to reach out if you have any additional questions beyond that :)

Answer 5

2x+1 = 9

subtract 1 from both sides to get

2x = 8

divide both sides by 2

x = 8/2 = 4

x = 4

Answer 6

Answer 7

For the equation 2x + 1 = 9. The goal is to find what value(s) for the variable x makes the equation true.

We want to first want to isolate the variable. Thus we take the +1 from the left side and move it to the right. We do this by subtracting 1 from both sides.

2x + 1 = 9

2x + 1 - 1 = 9 - 1

Add the ones together. You cannot add to the 2x. Because a number with a variable cannot add, subtract, multiply, or divide by a number without that same variable. Thus, you will continue to have 2x on the left.

So, we have:

2x + (1 - 1) = 9 - 1

2x + (0) = 8

So because we have a zero added to 2x, we can simply say:

2x = 8

Now we want to eliminate the 2 on the left. Since 2x is the same as 2 times x or (2*x), we will need to divide by 2 on both sides. Such as:

2x / 2 = 8 / 2

So now, the 2s will cancel because multiplying by 2 is the opposite of dividing by 2 so they will cancel.

Then we are left with:

x = 8 / 2

and 8 divided by 2 is 4. so now we think x = 4. To prove this we will substitute 4 in for x into the original equation and see again if the two sides are the same.

2x + 1 = 9 is the same as 2 * x + 1

[2 * (4)] + 1 =9

So now we will multiply 2 times 4 because x = 4.

8 + 1 = 9

9 = 9

So it confirmed that x = 4 when 2x + 1 = 9.

Answer 8

Solve 2x + 1 = 9

1. Subtract 1 from both sides to get 2x = 8
2. Divide both sides by 2 to get x = 4

Answer 9

2x+1=9

so' we know that'

2x=9-1

2x=8

x=8/2

x=4 and this is our answer

Answer 10

2x + 1 = 9

We can first combine like terms. The thing to keep in mind while doing a question this is that we need to isolate x since we are solving for x and in order to do that we must get rid of everything else which is move everything other than the x to the other side of the equal sign.

First step: Combine like terms

Since 1 and 9 are like terms we can combine them. They are on different sides of the equal sign so we can subtract 1 from both sides to do that and since it is +1, we do the opposite which is subtract 1:

2x + 1 - 1 = 9 - 1

2x = 8

Second step: Isolating x

Remember we need to get x by itself but we have the 2 that we need to get rid of with the x. Since 2 is being multiplied with the x, we do the opposite which is divide by 2 on both sides:

2x/2 = 8/2

x = 4

Therefore, x = 4.

Answer 11

Mental steps

Solve means to find a number for x (value for the variable).

Equation means an algebraic expression = another algebraic equation (2x + 1 and 9)

steps are the mathy things you do to the equation

solution is the number that x is

2x means 2 times x

Written steps

eliminate a number in the expression with x (+ - is easier) by doing the inverse (opposite)

2x + 1 - 1 = 9 - 1

Then simplify

1 - 1 = 0 and 9 - 1 = 8

2x + 0 = 8

2x + 0 is 2x

2x = 8

Now eliminate 2 using ÷ because 2x is times

2x÷2 = 8÷2

simplify

1x = 4

x = 4 (1 times x is just x just like 1 times 5 is just 5)

x = 4 is the SOLUTION

Answer 12

Consider the equation of 2x+1=9.

Then we have 2x+1=9,

2x=9-1,

2x=8,

x=8/2.

Thus, x=4.

Therefore, x=4.