Final answer:
A straighter line on a line graph indicates a stronger relationship between the two variables.
Step-by-step explanation:
In a line graph, a straighter line indicates a stronger relationship between the two variables. So, the statement "The straighter the line on a line graph, the weaker the relationship between the two variables" is False.
When line A is a decreasing line and line B is an increasing line, with line B being much steeper than line A, it means that line B has a higher slope than line A. A steeper line indicates a stronger relationship between the variables as a change in one variable leads to a larger change in the other variable.
Therefore, the correct answer is False.