Keys: on the board, press 1 or 2 to pick a tip, or V to pick the target. Press [ or ] to step through the tips. Press an arrow key to move the picked tip one snap step. Hold Shift with an arrow key to move it five snap steps.
Scalars
Hand solution
Matrix equation
R
Board
Snap step
On each line of the combination grid, x1 or x2 is a whole number. The crossings are the combinations with whole-number scalars.