How do you multiply $(7q - 5)(7q + 5)$ ?

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Answer 1 · 2016-02-26T15:30:23

$=49q^2 -25$

$(7q-5) (7q+5)$

The above expression is of the form:
$color(blue)((a-b)(a+b) = a^2-b^2$

Applying the above property:

$7q = color(blue)(a$
$5 = color(blue)(b$

$(7q-5) (7q+5) = (7q)^2 - 5^2$

$=49q^2 -25$

How do you multiply (7q - 5)(7q + 5)(7q - 5)(7q + 5)?