multiply (4x-7)(4x+7)

Question

I need this problem solved, please.

 

Answer 1

_{(4x - 7)(4x + 7)}

 

(4x)(4x) + (4x)(7) - 7(4x) - (7)(7)

 

16x² + 28x - 28x - 49

 

16x² - 49

 

 

 

Answer 2

There is a pattern here.  (A+B)(A-B)=A²-AB+AB-B²=A²-B², You should remember it, it's really handy.