please help me urgent.if you noo any answer please help me. if you don't know don't type
Answers
if you liked the ans do mark as brainliest
Question :-
Factorise the following equations ;
- 1. 9x² + 12xy + 4y²
- 2. 16x² + 8xy + y²
- 3. 16x² - 8xy + y²
Answer :-
Given :-
Equations ;
- 1. 9x² + 12xy + 4y²
- 2. 16x² + 8xy + y²
- 3. 16x² - 8xy + y²
Required to find :-
- Factorise the given equations ?
Identities used :-
- ( a + b )² = a² + 2ab + b²
- ( a - b )² = a² - 2ab + b²
Solution :-
1.
9x² + 12xy + 4y²
( 3x)² + 2 ( 3x )( 2y ) + ( 2y )²
This is in the form of ;
- ( a + b )² = a² + 2ab + b²
Here,
a = 3x
b = 2y
This implies ;
=> ( 3x + 2y)²
2.
16x² + 8xy + y²
( 4x )² + 2 ( 4x )( y ) + ( y )²
This is in the form of ;
- ( a + b )² = a² + 2ab + b²
Here,
a = 4x
b = y
This implies ;
=> ( 4x + y )²
3.
16x² - 8xy + y²
( 4x )² - 2 ( 4x )( y ) + ( y )²
This is in the form of ;
- ( a - b )² = a² - 2ab + b²
Here,
a = 4x
b = y
This implies ;
=> ( 4x - y )²
Therefore ;
The given quadratic equations in 2 variables had been factorised as follows ;
- 1. 9x² + 12xy + 4y² = ( 3x + 2y )²
- 2. 16x² + 8xy + y² = ( 4x + y )²
- 3. 16x² - 8xy + y² = ( 4x - y )²
Additional Information :-
How to verify whether the factorisation is correct or wrong ?
Answer :-
To verify whether the factorisation is correct or wrong for that we should multiply the factors which we got by factorisation .
So,
Let me explain you with an example .
Example :-
From the above it is clear that ;
9x² + 12xy + 4y² = ( 3x + 2y )²
So
Multiplying ( 3x + 2y ) twice will gives us the equation back .
Let's prove it ;
( 3x + 2y ) ( 3x + 2y ) = 9x² + 12xy + 4y²
3x ( 3x + 2y ) + 2y ( 3x + 2y ) = 9x² + 12xy + 4y²
9x² + 6xy + 6xy + 4y² = 9x² + 12xy + 4y²
9x² + 12xy + 4y² = 9x² + 12xy + 4y²
LHS = RHS
Hence verified ✔️
This trick is very useful when dealing with complicated factorisations .