Each line has two handles: the round b handle on the y-axis slides the line up and down, and the diamond m handle turns it. Handles snap to whole numbers. Keyboard: focus the graph, press 1 to 4 to pick a handle, then use the arrow keys. Or type a slope (like −3/4) and an intercept in the boxes.
Your job
Fictional people and practice numbers to learn the math.
Wrong picks are fine here. Each one tells you why.