Question

How do you solve for x in $2x - a = b$ ?

Answer 1

Hint:In this question, an algebraic expression containing three unknown variable quantities is given to us. We have to solve this question for x, so we treat other alphabets as constant. For finding the value, we will rearrange the equation such that x lies on one side of the equation and all other terms lie on the other side. As “a” is in subtraction on the left-hand side, so it will be in addition on the right- hand side, then we will divide both the sides by 2 to get the value of x.

Complete step by step answer:
We are given that $2x - a = b$
To find the value of x, we will take $a$ to the right-hand side so that the terms containing x are present on one side and the constant terms are present on the other side –
$ \Rightarrow 2x = b + a$
Now, we will take 2 to the right-hand side –
$x = \dfrac{{a + b}}{2}$
Hence, when $2x - a = b$ , we get $x = \dfrac{{a + b}}{2}$ .

Note: We note that we need an “n” number of equations to find the value of “n” unknown variables. So to find the value of each unknown variable we need 3 equations, but in the given question, we have to solve for x. So, we treat the other unknown variables as constant, now we have 1 unknown quantity and exactly one equation to find the value of x. We can get the value of x by putting the values of w and b in the obtained equation.