Question
Use the direct method to evaluate the following products : $(8 – b) (3 + b)$
✓
Answer
$(8 – b) (3 + b) $
$= (8 \times 3) + (8 \times b) + (−b \times 3) + (−b \times b)= 24 + 8b − 3b − b^2$
$= 24 + 5b − b^2$
$= (8 \times 3) + (8 \times b) + (−b \times 3) + (−b \times b)= 24 + 8b − 3b − b^2$
$= 24 + 5b − b^2$
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