How do you multiply #(7-8x)(7+8x)#?

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Answer 1 · 2015-12-03T07:50:32

#=color(blue)(49-64x^2#

#(7−8x)(7+8x)#

Upon observation it can be noticed that the expression is of the form:

#color(blue)((a-b)(a+b) = a^2-b^2#

So, in the given expression:

#7=color(blue)(a) and 8x=color(blue)(b#

#(7−8x)(7+8x) = 7^2-(8x)^2#

#=color(blue)(49-64x^2#