Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to make two linear equations which go through (5, 4): one with a negative slope and one with a positive slope. You may reuse all the integers for each equation. Source: Robert Kaplinsky

Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to make a product that is as close to zero as possible without being exactly zero. Source: Robert Kaplinsky

Directions: Using the integers -9 to 9, at most one time each, place an integer in each box twice to make a positive product and a negative product. You may reuse all the integers each product. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to make the greatest possible irrational number. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to make the statement true. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to create supplementary and complementary angles where the measures of each pair of angles are as close together as possible. Source: Brian Anderson with Robert Kaplinsky

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to create a circle with the smallest difference between the area estimates. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to create two possible circles. You may reuse all the digits for each statement. Source: Robert Kaplinsky

Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to create a quotient with the greatest possible value. Source: Robert Kaplinsky

Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to create two equations. You may reuse all the integers for each equation. Source: Robert Kaplinsky