We can use the exact same logic. When x becomes a very, very negative number, as it becomes further and further to the left on the number line, the only terms that are going to matter are going to be the 4x to the 5th and the 6x to the 5th. So this is true for very large x's. It's also true for very negative x's. So we could also say as x approaches negative infinity, this is also true. Then the x to the 5th over the x to the 5th is going to cancel out. These are the dominant terms.