Question
Simplify the following using the formula $(a + b)^2= a^2+ 2ab + b^2:$
$(82)^2-(18)^2$
$(82)^2-(18)^2$
✓
Answer
Here, we will use the identity $(a - b) (a + b) = a^2- b^2$
Let us consider the following expression:
$(82)^2-(18)^2$
$= (82 + 18)(82 - 18)$
$= 100 × 64$
$= 6400$
Let us consider the following expression:
$(82)^2-(18)^2$
$= (82 + 18)(82 - 18)$
$= 100 × 64$
$= 6400$
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