Why is it useful to know the definition of rational expression? explain through an example of your own?

It is important to know rational expression because we come across rational expressions most of the time in the real world, often without even realizing it.

Example: you may want to know how much of a 25% chemical solution need to be added to 1L of water to produce a 10% solution.

Ans: Equation:

solution + water = solution

0.25x + 0*1 L = 0.10 (x+1)

Multiply the above equation by 100 to get:

25x + 0 = 10x + 10

15x = 10

x = 2/3 Liter (amt. of 25% solution in the mixture)