• Students understand that if a number sentence is true and we make any of the following changes to the
number sentence, the resulting number sentence will be true:
i. Adding the same number to both sides of the equation
If a = b then a + c = b + c
ii. Subtracting the same number from both sides of the equation
If a = b then a - c = b - c
iii. Multiplying each side of the equation by the same number
If a = b then a(c) = b(c)
iv. Dividing each side of the equation by the same nonzero number
If a = b and c ≠ 0 then a ÷ c = b ÷ c
• Students revisit the integer game to justify the above referenced if-then statements.
• If a number sentence is true, a = b, and you add or subtract the same number from both sides of the
equation, then the resulting number sentence will be true.
• If a number sentence is true, a = b, and you multiply or divide both sides of the equation by the same
number, then the resulting number sentence will be true.