Which expressions are equivalent to 16x4 − 64? check all that apply.
16x4 + 16x – 16x – 64
16x4 – 8x – 8x – 64
(4x2 + 8)(4x2 – 8)
16(x2 + 2)(x2 – 2)
4(4x4 – 8)

The first one is one, because 16x and -16x cancel eachother out, the second one on the other hand is not because 2 negatives do not cancel each other, but instead, add together. the third one yes, because when you foil 4x2 times 4x2 = 16x4. the -8 x 4x2 and 8 x 4x2 cancel eachother out, leaving you with -8 x 8, which equals -64, thus 16x4 - 64. the 4th one yes, because 16x2 x x2 = 16x4, and 16 x 2 = 32, x -2 equals -64.the last one, no because while 4 x 4x4 IS 16x4, 4 x -8 is 32 

What the heck don’t understand