Open Middle®
Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to create two perpendicular lines.
Hint
How can you algebraically verify that your lines are perpendicular? How can you graphically verify that your lines are perpendicular?
Answer
There are many possible answers including:
y = 2/3x + 5
6x + 4y = 8
y = 2/3x + 5
6x + 4y = 8
Source: Robert Kaplinsky