Question

write down the following products

1. (3b+7) (3b-7)

2. (9a+10b) (9a - 10 b)

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Answer 1

Answer:

1. ( 3b )^2 - (7) ^2

2. (9a)^2 - (10b )^2

Answer 2

Step-by-step explanation:

$1. \: \: (3b + 7) \: (3b - 7) \\ {(3b)}^{2} - {(7)}^{2} \\ 9 {b}^{2} - 49 \\ \\ 2. \: \: (9b + 10b) \: (9b - 10b) \\ {(9b)}^{2} - {(10b)}^{2} \\ 81 {b}^{2} - 100 {b}^{2} \\ - 19 {b}^{2}$