Question

Write the verbal sentence as an equation and also solve this

“Fifteen plus a number is equal to21minus the number”

Short answer

The equation is $15+x=21-x$ and the solution is $x=3$.

Step-by-step solution

Step  1  . Apply the concept of linear equation

In this, simply use the concept of making a linear equation by understand the statement carefully and then solve it by doing various mathematical operations.

Step  2  . Find the equation

Here, the statement is : Fifteen plus a number is equal to 21 minus the number

Since,

Let the number be x.

15 plus the number, gives- 15+x

It is also given that it is equal to 21 minus of the number- 21-x

So, the final equation becomes: 15+x=21-x.

Step -3 – Solving the equation

The equation is$15+x=21-x$ .

Simple open the bracket and make the variable and constant of the separate side and do mathematical operations,

$\begin{array}{l}15+x=21-x\\ x+x=21-15\\ 2x=6\\ x=\frac{6}{2}\\ x=3\end{array}$