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Question
Use suitable identity to find the following product:
(x + 8) (x – 10)
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Solution
By using the identity (x + a)(x + b) = x2 + (a + b)x + ab,
(x + 8)(x – 10) = x2 + (8 – 10)x (8)(–10)
= x2 + (–2)x + (–80)
= x2 – 2x – 80
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