Question
Use the direct method to evaluate the following products : $(b – 3) (b – 5)$
✓
Answer
$(b – 3) (b – 5) $
$= (b \times b) + (b \times −5) + (−3) \times b + (−3) (−5)$
$= b^2 − 5b − 3b + 15$
$= b^2− 8b + 15$
$= (b \times b) + (b \times −5) + (−3) \times b + (−3) (−5)$
$= b^2 − 5b − 3b + 15$
$= b^2− 8b + 15$
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