Question

How do you solve\[2x-9=15\]?

Answer 1

Hint: In this type of question, we will arrange the equation by solving the equation in the standard form of x=C. We will take the variables to the left side of the equation and all the constants to the right side of the equation so that equation is balanced. After balancing the equation, we will solve and find the value of x.

Complete step by step answer:
Let us solve this question.
The equation which we have to solve is given in question.
The equation is
\[2x-9=15\]
As we know that the standard form of linear equation is always having the highest degree of 1 and the form of linear equation is x=C. So, we will make the given equation in that form.
First, we will balance the given equation. After that we will find the find value of x.
If we have to balance the equation, then the equation 2x-9=15 also can be written as
\[\Rightarrow 2x-9+9=15+9\]
The above equation can also be written as
\[\Rightarrow 2x=15+9\]
The above equation can also be written as
\[\Rightarrow 2x=24\]
Now, we will write the above equation by dividing both the sides of the equation by 2. We get the equation as
\[\Rightarrow \dfrac{2x}{2}=\dfrac{24}{2}\]
So, on the left side of equation, 2 will be cancelled out and on the right side of equation 24 is divided by 2. So, we will get 12 on the right side of the equation. Because 24 is multiple of 12 and 2
So, we can write the above equation as
\[\Rightarrow x=12\]
So, we have solved the equation\[2x-9=15\]and got the value of x as 12.

Note:
Always remember that the equation having highest degree 1 or we can say the equation which is linear has always one solution. We have an alternate method to solve this question.
We can solve this question using additional subtraction property.
As the given equation is\[2x-9=15\].
So, in this equation, the number -9 which is in the left side of the equation, we will take -9 to the right side of the equation. Now, the number -9 will change the sign if it goes to the right side of the equation. it will be +9.
The equation can also be written as
\[\Rightarrow 2x=15+9\]
\[\Rightarrow 2x=24\]
We know that 24 can be written as the multiple of 12 and 2. So, 2 will be cancelled out on both sides.
Hence, we can write the above equation as
\[\Rightarrow x=12\]