K represents the slope of a straight line,
When the angle between the straight line and the positive direction of the X axis is less than 90 degrees and greater than 0 degrees, the larger the angle, the greater the K;
When the angle between the straight line and the positive direction of the X axis is less than 180 degrees and more than 90 degrees, the larger the angle, the smaller the K. 。
The solution is as follows
According to the topic, we can establish the following inequality: 80× x
Using the mathematical equation, we can express it as: 80x.
Now