Step-by-step explanation:
6k + 12 + 9=9
6k + 12 = 9 - 9
6k + 12 = 0
12 = -6k
12/-6 = -6k/-6
2/-1 = k
k = -2
There fists meet after 3 seconds
30 x 3=90
70 x 3=210
210+90=300
Goku at 90 mm
Vegeta at 210 mm
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