Question

Solve the following according to the given instructions (08)

Evaluate using suitableldentites.

1. (2a +7) (2a -7)​

Answer 1

Answer:

according to the given instructions (08) = ?

Lemme Try : -

(2a +7) (2a -7) = 0

=> 2a ( 2a - 7 ) + 7 ( 2a - 7 ) = 0

=> 4a^2 - 14a + 14a - 49 = 0

=> 4a^2 - 49 = 0

=> 4a^2 = 49

=> ( 2a ) ^2 = 7 ^2

i.e ,

2a = 7

Therefore ;

a = 7 / 2

or ,

3 ( 1 / 2 )

or ,

3.5

Also , Can be written in form of ;

( a^2 - b^2 )

As , ( a^2 - b^2 ) = ( a + b ) ( a - b )