Transcript for:
Introduction to Algebra

What is Algebra? It's simple. It's all about puzzles. Here's one for you. This plus two equals five. We just have to find the number in this box. Which number when added to two gives us five? Simple! It's three. We can say that three plus two equals five. This thing we see here contains only numbers. This puzzle can also be asked in a different way, We can say that x plus two equals five, find 'x'. We just used a letter in place of the box. These letters are also called as variables. Sometimes also referred to as the unknown since its values is not known to us. This is Algebra. It deals with variables and unknowns and we are expected to find their value. But why use variables? Why not boxes like these? Let's assume there are three unknown numbers. Using shapes we can write it as a square, plus a slant square, plus an empty circle, plus four equals seven. You had to think of different shapes. Using variables we can write it as x plus y plus z plus four equals seven. This was a little more convenient as compared to the previous case. But what's the real advantage of using variables? Read the short story and the question that follows. Your friend had a few chocolates with him. A bully came across, took away five of his chocolates. And then he had just seven chocolates remaining with him. How many chocolates did he have before the bully came to him? This question has '40 words'. Let's see if it can shorten the question a bit. Assume your friend had 'x' chocolates with him. The bully took away five of his chocolates, so we subtract five from 'x'. And after all this your friend was left with seven chocolates. This entire thing, will then equal seven. Now all we have to do is find 'x'. This entire question of '40 words' can be written like this. So yes, Algebra makes life simple.