Question

use a suitable indenity and solve {4b+9}{4b+7}
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Answer 1

Step-by-step explanation:

$identity \: used \: = (x + a)(x + b) \\ = {x}^{2} + (a + b)x + ab \\ \\ ({4b})^{2} + (9 + 7)4b + 9 \times 7 \\ = {16b}^{2} + (16)4b + 63 \\ = {16b}^{2} + 64b + 63$