Subtraction of Algebraic Expression

In Subtraction of Algebraic Expression from another,follow the following steps

1) Change the signs.

‘+’ ---> ‘- ‘

‘-‘ ----->’+’ of all the expressions which is to be subtracted and then the two expressions are added.
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2)Then add two expressions.

Example :

1) Subtract -7x from 5x

Solution :

= 5x – ( -7x)
=5x + 7x
= 12x
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2)x² + y² + 3xy from 4x² + 2xy – 3y²

Solution :

=(4x² + 2xy – 3y²) – (x² + y² + 3xy)
= 4x² + 2xy – 3y² - x² - y² - 3xy
=4x² + 2xy – 3y² - x² – y² - 3xy
= 3x² - xy – 4y²
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3)What should be subtracted from a³ - 4a² + 5a – 6 to obtain
a² - 2a + 1 ?

Solution:

Let 'X' denote the required expression,
(a³ - 4a² + 5a – 6) – X = a² - 2a + 1
Hence , X = (a³ - 4a² + 5a – 6) – (a² - 2a + 1)
= a³ - 4a² + 5a – 6 - a² + 2a – 1
= a³ - 4a² +5a – 6 - a² +2a –1
= a³ - 5a² + 7a – 7
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4)Subtract a³ - 4a² + 5a – 6 from the sum of 3a³ + a² + 1 and a² -2?

Solution:

= [(3a³ + a² + 1) + a² -2)] - (a³ - 4a² + 5a – 6 )
= (3a³ + a² + 1+ a² -2) - (a³ - 4a² + 5a – 6 )
= (3a³ + 2a² -1) - (a³ - 4a² + 5a – 6 )
= 3a³ + 2a² -1 - a³ + 4a² - 5a + 6
= 3a³ + 2a² -1 - a³ + 4a² - 5a + 6
= 2a³ + 6a² - 5a + 5

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Algebraic Expressions

• Like and Unlike terms in Algebra
• Addition of algebraic expressions
• Subtraction of algebraic expressions
• Multiplication of algebraic expressions
• Division of algebraic expressions
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