Question

How do you solve: $\dfrac{2}{7}x-3=-8$?

Answer 1

Hint: Multiply both the sides of the given equation with 7 to remove the fractional term. Now, rearrange the terms of the given equation by leaving the terms containing the variable x to the L.H.S. and taking the constant terms to the R.H.S. Now, use simple arithmetic operations, like: addition, subtraction, multiplication or division, whichever needed, to simplify the equation. Make the coefficient of x equal to 1 and accordingly change the R.H.S. to get the answer.

Complete step by step solution:
Here, we have been provided with the equation: $\dfrac{2}{7}x-3=-8$ and we are asked to solve this equation. That means we have to find the value of x.
$\because \dfrac{2}{7}x-3=-8$
Multiplying both the sides with 7 to remove the fraction in the L.H.S we get,
$\Rightarrow 2x-21=-56$
As we can see that the given equation is a linear equation in one variable which is x. So, leaving the terms containing the variable x to the L.H.S. and taking the constant terms to the R.H.S., we get,
\[\begin{align}
  & \Rightarrow 2x=21-56 \\
 & \Rightarrow 2x=-35 \\
\end{align}\]
Dividing both the sides with 2, we get,
\[\Rightarrow x=\dfrac{-35}{2}\]
Hence, the value of x is \[\dfrac{-35}{2}\].

Note: One may note that we have been provided with a single equation only. The reason is that we have to find the value of one variable, that is x. So, in general if we have to solve an equation having ‘n’ number of variables then we should be provided with ‘n’ number of equations. You can check the answer by substituting the obtained value of x in the equation provided in the question. You have to determine the value of L.H.S. and R.H.S. separately and if they are equal then our answer is correct.