Answer:
True, A linear equation determines a line in the xy-plane.
Explanation:
A linear equation is in the form of Px + Qy = R where P , Q and R are constants.
Let us take an example 2x +3y = 6
When we plot the above equation in graph we get a line in xy plane.(as shown below) Since, there are two variables, x and y, then will it be possible, only on the xy plane.
It is also clear from the graph that linear equation shows the relation between x and y axis. Thus, it is true to say a linear equation determines a line in the xy-plane.