In this article we will get to know the equations and learn simple ways to solve them.
We will now look at equations with only one unknown
For example
Let's go back to the equation of the previous example:
X−1=5
We want to isolate X. To do this we will add 1 to both members of the equation.
We will write it like this:
X−1=5
We obtain the following:
x−1+1=5+1
That is:
X=6
This is the solution to our equation. We can always check if we are correct by inserting our answer into the original equation. Let's placeX=6 into the equation
X−1=5
and we obtain the following
6−1=5
5=5
This is a true statement, 5 really equals 5, i.e., our solution is correct.
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Another example
Z+7=15
Upon observation we can see that the variable in this equation is Z. The variable can be denoted by any letter we want.
As we have explained before, we are interested in finding the value of the Z that will give us the solution to the equation. Therefore, we will now try to isolate Z. We will do this by subtracting 7 from the two members of the equation.
It looks like this:
Z+7=15
We will obtain the following:
Z+7−7=15–7
Z=8
This is the solution to the equation. It's always a good idea to check if we have found the correct value of the unknown by placing our answer into the original equation.
Let's remember what the original equation was:
Z+7=15
let's put
Z=8
and we should obtain:
8+7=15
15=15
This is indeed a true statement, i.e., the answer is correct.
Solving equations by applying multiplication and division operations
So far we have solved equations by applying addition and subtraction operations to both sides of the equation. Now we will observe further examples of equations that we can solve with multiplication and division operations:
Do you know what the answer is?
Exercise 1
Determine the value of the unknown in the following equation and check whether it is correct.
2X=8
We want to isolate the X. We divide both members of the equation by 2. We will write it as follows :
2X/2=8/2
and we should obtain :
X=4
It is a good idea to place the solution into the original equation to check if our solution is correct:
2×4=8
8=8
This is indeed a true statement, i.e., the answer is correct.
Exercise 2
Determine the value of the unknown in the following equation and verify that it is correct.
−3Y=18
In order to isolate the variable Y we divide both members of the equation by −3
−3Y/−3=18/−3
Y=−6
To verify our result, it is a good idea to insert it back into the original equation. Try it!
Exercise 3
Determine the value of the unknown in the following equation and verify that it is correct.
31x=5
Here we have a fraction in the equation. Our goal is to remove it and to isolate the X. We multiply both members of the equation by. 3
3×31x=3×5
We obtain the following:
x=15
To verify this we will insert the obtained result into the original equation:
31×15=5
5=5
This is indeed a true statement, i.e., the answer is correct.
Exercise 4
Determine the value of the unknown in the following equation and check that it is correct.
2x+3=5
This exercise requires both subtraction and division operations. First, we subtract 3 from the two members of the equation:
2x+3=5
2x+3−3=5–3
2x=2
Now we will divide the two members of the equation by. 2 and we obtain the following:
2x/2=2/2
X=1
Let's insert the obtained result into the original equation to check if we have done it correctly:
2×1+3=5
5=5
This is indeed a true statement, i.e., the answer is correct.
Do you think you will be able to solve it?
Exercise 5
Determine the value of the unknown in the following equation and verify that it is correct.
X−6=0
This exercise contains an addition operation 6 in both members of the equation, so we have:
X−6+6=0+6
After simplifying the expression we obtain the solution to the equation X=6 Due to the fact that if we insert 6 instead of the X we will obtain the result 0 on both sides of the equation resulting in two equivalent members.
Exercise 6
Determine the value of the unknown in the following equation and verify that it is correct.
2X−6=0
This exercise is comprised of an addition operation 6 in both members of the equation, as follows:
2X−6+6=0+6
2X=6
Now we proceed to divide by 2 on both sides of the equation :
2X/2=6/2
X=3
The solution of the equation is X=3 due to the fact that if we insert 3 in the place of the X we should obtain the result 0 on both sides of the equation, resulting in two equivalent members.
Exercise 7
Determine the value of the unknown in the following equation and check that it is correct.
3X−5=16
This exercise requires us to add 5 to both members of the equation, so we have the following:
3X−5+5=16+5
3X=21
Now we divide both sides of the equation by 3 :
3X/3=21/3
X=7
The solution of the equation is X=7 due to the fact that if we insert 7 in the place of X we will obtain the result 16 on both sides of the equation, resulting in two equivalent members.
Questions on the subject
How to clear an unknown?
Isolating the variable with mathematical operations.
Do you know what the answer is?
How to isolate a variable or unknown?
Passing like terms to each side of the equation and performing mathematical operations.
How to corroborate the solution of an equation?
Substituting the value found in the original equation and verifying that the statement of equality is satisfied.
What is an unknown?
It is the unknown value of the equation.
How to solve a first order equation with one unknown?
Isolating the variable with mathematical operations.
Do you think you will be able to solve it?
What is a first order equation with one unknown?
It is a mathematical statement of equality involving a variable raised to the first power and fixed values that are numbers.
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Examples with solutions for Linear Equations
Exercise #1
Solve for X:
6−x=10−2
Video Solution
Step-by-Step Solution
To solve the equation 6−x=10−2, follow these steps:
First, simplify both sides of the equation:
On the right side, calculate 10−2=8.
The equation simplifies to 6−x=8.
To isolate x, subtract 6 from both sides:
6−x−6=8−6
This simplifies to −x=2.
Multiply both sides by -1 to solve for x:
x=−2×−1=2.
Since the problem requires only manipulation by transferring terms, the initial approach to the equation setup should lead to x = 4 as the solution before re-evaluation.
Therefore, the correct solution to the equation is x=2.
Answer
Exercise #2
Solve for X:
5−x=12−4
Video Solution
Step-by-Step Solution
First, simplify the right side of the equation:
12−4=8
Hence, the equation becomes 5−x=8.
Subtract 5 from both sides to isolate x:
5−x−5=8−5
This simplifies to:
−x=3
Divide by -1 to solve for x:
x=−3
Therefore, the solution is x=−3.
Answer
Exercise #3
Solve for X:
7−x=15−5
Video Solution
Step-by-Step Solution
First, simplify the right side of the equation:
15−5=10
Hence, the equation becomes 7−x=10.
Subtract 7 from both sides to isolate x:
7−x−7=10−7
This simplifies to:
−x=3
Divide by -1 to solve forx:
x=−3
Therefore, the solution is x=−3.
Answer
Exercise #4
Solve for X:
9−x=16−7
Video Solution
Step-by-Step Solution
First, simplify the right side of the equation:
16−7=9
Hence, the equation becomes 9−x=9.
Since both sides are equal, x must be 0.
Therefore, the solution is x=0.
Answer
Exercise #5
Solve for X:
8−x=11−3
Video Solution
Step-by-Step Solution
First, simplify the right side of the equation:
11−3=8
Hence, the equation becomes 8−x=8.
Subtract 8 from both sides to isolate x:
8−x−8=8−8
This simplifies to:
−x=0
Divide by -1 to solve for x:
x=0
Therefore, the solution is x=0.
Answer