Question
Use the direct method to evaluate the following products : $(a – 8) (a + 2)$
✓
Answer
$(a – 8) (a + 2) $
$= (a \times a) + (a \times 2) + (−8)\times a + (−8)(2)$
$= a^2+ 2a − 8a − 16$
$= a^2 − 6a − 16$
$= (a \times a) + (a \times 2) + (−8)\times a + (−8)(2)$
$= a^2+ 2a − 8a − 16$
$= a^2 − 6a − 16$
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