Page 222 - Start Up Mathematics_6

At a Glance

1. Algebra is a branch of Mathematics in which letters (characters of the English alphabet)
are used to represent a number.
2. If letters are used to denote numbers, they are called literals.

3. The quantities with fixed numerical values are called constants.
4. Variables are quantities that can take any value.

5. An algebraic expression is a combination of variables and constants using all or some of the
fundamental operations.

6. An equation is a condition on a variable which is satisfied by a definite value of a variable.
The value of the variable which satisfies the given equation is its solution.

Review Exercises

Multiple ChoiCe Questions

1. The expression 5 reduced from 3 times x is:
(a) 5x – 3 (b) 5 – 3x (c) 3x + 5 (d) 3x – 5
2. The solution of the equation 3x + 4 = 1 is:
(a) 1 (b) 0 (c) –1 (d) 2
3. If there are x chairs in a row, then the number of students that can be seated in 7 rows are:
(a) 7 + x (b) 7x (c) 35 (d) x 2
4. The rule that gives the number of matchsticks required to make the following pattern containing
n hexagons is:

, ,
, ....
(a) 5n (b) 6n (c) 5n + 1 (d) 6n + 1

5. Observe the pattern of digit 8 formed using matchsticks of different lengths.

, , , ....

The number of matchsticks required for a pattern containing hundred 8’s is:

(a) 500 (b) 501 (c) 502 (d) 700
6. The property of numbers which says 3 × 42 is equal to 3 × 40 + 3 × 2 is known as:
(a) commutative (b) associative (c) distributive (d) none of these

solve Mentally
True or False

1. Literal, like variable is a term that does not have a fixed value.
2. The expression 4x is a variable.

3. The number of angles in a quadrilateral is a variable.

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