Expressions & Equations

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

Directions: Using the integers -9 to 9 at most one time each, place an integer in each box to make a value that is as close to zero as possible without being exactly 0. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the integers -9 to 9 at most one time each, place an integer in each box to make the least possible value. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the integers -8 to 8 at most one time each, place an integer in each box to make the greatest possible value. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the integers -9 to 9 at most one time each, place an integer in each box to make two values: one that is positive and one that is negative. You may reuse all the integers each time. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the digits 1 to 9 at most twice each, make the sum of the four expressions the greatest possible value. Source: Catriona Shearer

Directions: Using the integers -9 to 9 (excluding 0) at most one time each, fill in the blanks to create two distinct perpendicular lines. Source: Louise Pepper with answers from the students of Kings College Alicante, Spain

Directions: Using the digits 1 to 9, at most one time each, fill in the boxes to make a product that equals 800,000,000. Source: Robert Kaplinsky