Importance of Brackets

Summary

LearnNext Lesson Video

Using brackets
Brackets help in simplifying an expression that has more than one mathematical operation.
If an expression that includes the brackets is given, then perform the operation inside the bracket and change every thing into a single number. Then carry out the operation that lies outside the bracket.
e.g.
1. (6 + 8) x 10 = 14 x 10 = 140

2. (8 + 3) (9 - 4) = 11 x 5 = 55

Expanding brackets
The use of brackets allows us to follow a certain procedure to expand the brackets systematically.

e.g.

  1. 8 x 109 = 8 x (100 + 9) = 8 x 100 + 8 x 9 = 800 + 72 = 872

  2. 105 x 108 = (100 + 5) x (100 + 8)

                         =  (100 + 5) x 100 + (100 + 5) x 8

                         = (100 x 100) + (5 x 100) + (100 x 8) + (5 x 8)

                         = 10000 + 500 + 800 + 40

                         = 11340.

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