A presentation on Algebraic Expression

1. Algebraic Expressions
CLASS - VII and VIII
Prepared by
Golam Robbani Ahmed

2. Definitions
Variable – A variable is a
letter or symbol that
represents a number
(unknown quantity).
8 + n = 12

3. Definitions
Algebraic expression – an
expression that contains at least
one variable, operation, and
constant
m + 8
r – 3

4. Definitions
A constant is a number that does
not change.
A coefficient is a number multiplied
or divided by a variable.
6x + 5
6 is the coefficient, x is the variable,
and 5 is the constant.

5. Example
Here
2 is the coefficient, x
is the variable, 4 is
the coefficient, y is
variable
and 9 is the constant

7. Definitions
 A term is a part of an expression that are
added or subtracted
5x + 6 – 4x
This expression has 3 terms: 5x, 6, and 4x
 A like term are terms that has the same
variable raised to the same power
In the expression above, 5x and 4x are
like terms

9. Addition and Subtraction of Algebraic Expressions
We add the expression together on the same line and
arrange the like term together
2) Add the like terms
3) Write the Final algebraic expression
Example
Add the following expression x – y + xy, y – z + yz, z – x
+ zx
Solution:
= (x – y + xy)+( y – z + yz)+( z – x + zx)
Arranging the like term together
= x-x -y+y-z+z+xy+yz+zx (as x-x = y-y = z-z=0 )
=xy+yz+zx

10. Multiplication of Algebraic expression
General steps for Multiplication
1) We have to use distributive law and distribute
each term of the first polynomial to every term of
the second polynomial.
2) when you multiply two terms together you
must multiply the coefficient (numbers) and add
the exponents
3) Also as we already know ++ equals +
+- or -+ equals –
and -- equals +

11. Multiplication may involve
a) Multiplication of monomial to
monomial
b) Multiplication of monomial to
binomial, trinomial or more terms
polynomials
c) Multiplication of binomial, trinomial
or more terms polynomials to
monomial
d) Multiplication of binomial to
binomial, trinomial or more terms