Question

How do you solve 5x + 12 = x – 4?

Answer 1

Hint:
The above question is a simple problem of linear equations in one variable. So, we will simply first understand the concept and definition of linear equation in one variable and then we will solve the above question to get the value of ‘x’.

Complete step by step answer:
We know that the linear equation in one variable is an equation that has a maximum of one variable in the equation which is of order 1. Also, we know that a linear equation in one variable has only one solution.
And, also the standard form of linear equation in one variable is represented as:
ax + b = 0 where a, b is real number and a is not equal to zero.
So, we can say that 5x + 12 = x – 4 is a linear equation in one variable with variable x.
So, to solve 5x + 12 = x – 4 we will shift the variable on one side of the equation from another side of the equation and similarly, we will shift constant on the same side of the equation.
So, after shifting we will get:
$\Rightarrow 5x-x=-4-12$
$\Rightarrow 4x=-16$
So, after cancelation or dividing both side by 4 we will get:
$\Rightarrow x=-4$
Now, when we will put x = -4 in the equation, then we will get -8 = -8, which satisfies the equality.
Hence, x = -4 is our required answer.

Note:
Students are required to note that when we shift variable or constant from one side of the equation to the other side of the equation then the sign of the variable gets reversed and the magnitude remains the same. We can also try substituting values of x and checking if it satisfies the equation. But, it will be time-consuming and is not the best method.