Solving Simple Equations
Solving simple equations is one of the basic skills in algebra. An equation is like a scale where both sides are equal. The goal is to find the value of an unknown variable, usually represented by a letter like x
, that makes the equation true. Let's understand how to solve these equations step by step with clear examples.
What is the equation?
An equation is a mathematical statement that shows equality between two expressions. It has two sides: left side and right side. Here's what a simple equation looks like:
3 + x = 7
In this equation, 3 + x
is the left side, and 7
is the right side. Our task is to find what value of x
makes both sides equal.
Concept of balance scale
Think of the equation like a balance scale. Whatever you do on one side of the equation to maintain balance, you must do the same on the other side.
If you add, subtract, multiply, or divide one side, you must do the same to the other side to keep it balanced.
Steps to solve simple equations
Step 1: Isolate the variables
The first step is to bring the unknown variable to one side of the equation. You can do this by performing operations that will cancel out the other numbers or variables around it.
Consider the equation:
3 + x = 7
To get x
alone, you subtract 3
from both sides:
3 + x - 3 = 7 - 3
The simplification of which is as follows:
x = 4
Example 1
Let's solve the equation x - 5 = 10
.
To get x
alone, add 5
to both sides:
x - 5 + 5 = 10 + 5
so,
x = 15
Step 2: Simplify each side
Make sure each side of your equation is as simple as possible. Sometimes, you may need to combine or distribute like terms.
For example:
2x + 3x = 10
Combine like terms 2x
and 3x
:
5x = 10
Now divide both sides by 5
to find the value of x
:
5x / 5 = 10 / 5
like this,
x = 2
Example 2
Solve the equation 4(x - 1) = 12
.
First, distribute 4
:
4 * x - 4 * 1 = 12
The simplification of which is as follows:
4x - 4 = 12
Add 4
to both sides:
4x - 4 + 4 = 12 + 4
So it becomes:
4x = 16
Finally, divide both sides by 4
:
x = 16 / 4
Due to this:
x = 4
Step 3: Check your solution
Always plug the values back into the original equation to make sure your solution is correct. For the equation 3 + x = 7
, check if we get x = 4
:
3 + 4 = 7
Since this statement is true, the solution is correct.
Example 3
Let's check our solution for the equation 2x + 3 = 9
.
We get that x = 3
Substitute x = 3
back into the original equation:
2 * 3 + 3 = 9
Calculate:
6 + 3 = 9
Since this is true, our solution is verified.
Common mistakes and tips
When solving simple equations, avoid these common mistakes:
- Not balancing both sides of an equation: Always perform the same operation on both sides.
- Forgetting to simplify: Combine like terms and simplify each side whenever possible.
- Skipping the verification step: Always substitute your solution into the original equation to check your work.
Practice problems
Try solving these equations yourself and check your answers:
x + 6 = 15
2x - 8 = 0
3(x + 1) = 12
5x = 20
10 - x = 3
Solution:
x = 9
x = 4
x = 3
x = 4
x = 7
Conclusion
Understanding how to solve simple equations is fundamental in algebra. Remember to always perform the same operation on both sides of the equation and check your solutions by substituting them back into the original equation. Practice regularly to become more familiar and comfortable solving different types of equations.