How do you find the product (6y-7)(6y+7)(6y−7)(6y+7)?
1 Answer
Apr 22, 2017
Explanation:
Each term in the second bracket is multiplied by each term in the first bracket. This can be achieved as follows.
(color(red)(6y-7))(6y+7)(6y−7)(6y+7)
=color(red)(6y)(6y+7)color(red)(-7)(6y+7)=6y(6y+7)−7(6y+7)
=(color(red)(6y)xx6y)+(color(red)(6y)xx7)+(color(red)(-7)xx6y)+(color(red)(-7)xx7)=(6y×6y)+(6y×7)+(−7×6y)+(−7×7)
=36y^2+42y-42y-49=36y2+42y−42y−49
=36y^2-49larrcolor(magenta)" difference of squares"=36y2−49← difference of squares
