Question

Solve the following questions: \[5 - d = 12\]

Answer 1

Hint: Here we are asked to solve the given expression. As we can see that the given expression contains an unknown variable \[d\] so we have to find its value. This can be done by a simple method called the transposition method that is keeping the unknown variable on one side and moving the other terms to the other side. Then solving that side will give the value of the unknown variable.

Complete step by step answer:
It is given that \[5 - d = 12\] this is a simple linear equation with an unknown variable \[d\]. We aim to solve this simple equation, that is we need to find the value of the unknown variable \[d\].
Solving a simple equation can be done by an easy method called the transposition method. In this method, we will try to keep the unknown variable on one side of the equation by transposing the other terms to the other side.
Consider the given equation \[5 - d = 12\], here the unknown variable is \[d\] so we need to keep \[d\] on one side and transfer the other terms to another side.
Now let us take the term \[5\] from the left-hand side to the right-hand side. On transferring their sign, we get changed. So, the term \[5\] will become \[ - 5\].
\[5 - d = 12 \Rightarrow - d = 12 - 5\]
Now we can see that the unknown variable is in a negative sign. To make it positive let us multiply the whole equation by \[ - 1\].
\[ - d = 12 - 5 \Rightarrow d = 5 - 12\]
On simplifying the above, we get
\[d = - 7\]
Thus, we have found the value of the unknown variable \[d\].

Note:
In mathematics, a simple equation can be solved by using three methods: trial and error, systematic, and the transposition method. Here we have used a transposition method because it takes less time for calculation than the other two methods. Also, we can check whether our answer is correct or not by substituting the value of the unknown variable in the given equation, it satisfies the equation then the answer is correct.