Question

How do you solve \[3x\, = \, - 21\] ?

Answer 1

Hint: This is a very simple question. In this question, our aim is to solve and find the value of the variable \[x\]. By doing this our question will be solved. We can divide similar terms of the numerator by the denominator.

Complete step by step solution:
According to this question, we know that we have to find the value of the variable \[x\]. As we can see, the variable \[x\] is multiplied with the number \[3\] here. So, now we have to divide both the numerators of the equation by similar denominators respectively. After that we get:
\[ \dfrac{{3x}}{3} = \dfrac{{ - 21}}{3}\]
Now, the numerator and denominator is getting cancelled. After the cancellation, we get our final answer which is:
\[ \therefore x = \, - 7\]

So, on solving we get the equation as \[x = \, - 7\].

Additional information:
In this question \[3x\] is an algebraic expression having two terms. This expression means that \[3\] is multiplied with \[x\]. Many times the algebraic sum has more than one term as well. They can have the same structures or different structures as well. We need to solve the questions accordingly. In this question, there was only one term and one constant.

Note: The above method is very easy and the question is solved very quickly. But we have another method also. We can make the variable \[x\]be alone by shifting \[3\]to the other side. On that side \[3\] gets divided with \[ - 21\], and we get the answer as \[ - 7\]. This is also a very easy and direct method to get the answer. You can use any method from the two methods as per your convenience.