What causes the high tide (called the “opposite” tide) on the side of the earth furthermore from the moon?

The high tide on the opposite side of the Earth than the moon is on is because of the Moon's pull of gravity on the water.

Explanation: The reason for this is because the moon has its own pull of gravity on us. So when the moon is, say, highest over Asia, the tides over there will be lower. And when the moon is highest over Asia, the tides around the Americas will be higher.

wavelength divides in half and speed stays the same.