Find each of the following products:
(i) (x + 3)(x – 3)
(ii) (2x + 5)(2x – 5)
(iii) (8 + x)(8 – x)
(iv) (7x + 11y)(7x – 11y)
(v) 
(vi) 
(vii)
(viii)
(ix) 
(i) Given,
(x + 3)(x – 3)
By using the formula (a + b) (a – b) = a2 – b2
We get;
= x(x + 3) – 3(x + 3)
= x2 + 3x – 3x – 9
= x2 – 9
(ii) Given,
(2x + 5)(2x – 5)
By using the formula (a + b) (a – b) = a2 – b2
We get;
= 2x(2x + 5) – 5(2x + 5)
= 4x2 + 10x – 10x – 25
= 4x2 – 25
(iii) Given,
(8 + x)(8 – x)
By using the formula (a + b) (a – b) = a2 – b2
We get;
= 8(8 + x) – x(8 + x)
= 64 + 8x – 8x – x2
= 64 – x2
(iv) Given,
(7x + 11y)(7x – 11y)
By using the formula (a + b) (a – b) = a2 – b2
We get;
= 7x(7x + 11y) – 11y(7x + 11y)
= 49x2 + 77xy – 77xy – 121y2
= 49x2 – 121y2
(v) Given,
By using the formula (a + b) (a – b) = a2 – b2
We get;
(vi) 
By using the formula (a + b) (a – b) = a2 – b2
We get;
(vii) 
By using the formula (a + b) (a – b) = a2 – b2
We get;
(viii) 
By using the formula (a + b) (a – b) = a2 – b2
We get;
(ix) 
By using the formula (a + b) (a – b) = a2 – b2
We get;
