Question

How do you solve $4x - 9 = 51$?

Answer 1

Hint: In this question we have to solve the equation for $x$, the given equation is a linear equation as the degree of the highest exponent of $x$ is equal to 1. To solve the equation take all $x$ terms to one side and all constants to the others side and solve for required $x$.

Complete step by step solution:
Given equation is $4x - 9 = 51$, and we have to solve for $x$.
Given equation is a linear equation as the highest degree of $x$ will be equal to 1,
Now transform the equation by taking all $x$ terms to one side and all constants to the other side we get,
$ \Rightarrow 4x - 9 = 51$,
Now add 9 to both sides of the equation we get,
$ \Rightarrow 4x - 9 + 9 = 51 + 9$,
Now simplifying we get,
$ \Rightarrow 4x = 60$,
Now divide both sides with 4, we get,
$ \Rightarrow \dfrac{{4x}}{4} = \dfrac{{60}}{4}$,
Now simplifying we get,
$ \Rightarrow x = 15$,
So the value of $x$ will be 15, i.e., when we substitute the value of $x$ in the equation $4x - 9 = 51$, then right hand side of the equation will be equal to left hand side of the equation, we get,
$ \Rightarrow 4x - 9 = 51$,
Now substitute $x = 15$, we get,
$ \Rightarrow 4\left( {15} \right) - 9 = 51$,
Now simplifying we get,
$ \Rightarrow 60 - 9 = 51$,
Further simplifying we get,
$ \Rightarrow 51 = 51$,
So R.H.S=L.H.S.

$\therefore $ The value of $x$ when the equation $4x - 9 = 51$ is solved will be equal to 15.

Note: A linear equation is an equation of a straight line having a maximum of one variable. The degree of the variable will be equal to 1. To solve any equation in one variable, pit all the variable terms on the left hand side and all the numerical values on the right hand side to make the calculation solved easily.