Question

Write an expression for the model. Find the sum. options: a) 2 + (–3); 1 b) –3 + 2; 5 c) 2 + 3; 5 d) 2 + (–3); –1

Answer 1

c) 2 + 3 = 5 TRUE

d) 2 + (–3) = -1 True

Explanation:

When adding integers (positive and negative whole numbers), there are three cases:

• Positive and positive increases and sum is positive. Ex. 4 + 6 = 10
• Positive and negative where you subtract and take the sign of the larger number. Ex. 3 + -8 = -5 or -3 + 8 = 5
• Negative and negative decrease and the sum if negative. Ex. -4 + -6 = -10.

Use these rules to simplify each expression.

a) 2 + (–3) = -1 not 1 FALSE

b) –3 + 2 = -1 not 5 FALSE

c) 2 + 3 = 5 TRUE

d) 2 + (–3) = -1 True