(6 - 5x)(6 + 5x)=?
you need to visualize the foil method, Krill.
first start with the 6 in the first set and multiple with the second set <whole>
6 (6+5x) = 36+30x
second start with the -5x in the first set and multiple with the second set <whole>
-5x (6+5x) = -30x-25x^2
x^2 = x to the 2nd power
after the basic foil is done, you must combine all like terms.
x^2 terms may not be combine with 2x terms in short.
36-25x^2 should be your answer.