Question

How do you solve 4x+9=7x?

Answer 1

Hint: In this question, we are going to arrange the equation by making the equation in the standard form of linear equation. The standard form of the linear equation is x=C. We will take all the variables to the left side of the equation and all the constants to the right side of the equation. After that, we will solve the given equation to find the value of x.

Complete step-by-step answer:
Let us solve the question.
The given equation which we are going to solve is
4x+9=7x
We know that the standard form of linear equations having one variable is x=C, where x is any variable and C is constant.
For solving this equation, we will take all the variables to the left side of the equation and the constant to the right side of the equation.
Let us balance the equation.
4x+9-4x=7x-4x
\[\Rightarrow \]0+9=3x
\[\Rightarrow \]9=3x
Now, dividing 3 on both the sides of equation, we get
\[\Rightarrow \dfrac{9}{3}=\dfrac{3x}{3}\]
The above equation can also be written as
\[\Rightarrow 3=x\]
Hence, we get the value of x as 3 from the equation 4x+9=7x.

Note: Always remember that the linear equation having one variable has only one root.
If we want to check if we are correct or not, then we will cross-check for that.
For cross-checking, we will put the value of x as 3 in the given equation 4x+9=7x.
\[4\times 3+9=7\times 3\]
\[\Rightarrow 12+9=21\]
\[\Rightarrow 21=21\]
Hence, we get that the right side of the equation is equal to the left side of the equation.
So, our answer is correct.