Math Lab
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Integer Add and Subtract

Integers · Class VI

Slide two integers and see their sum and difference jump on the number line.

5
type a value
-2020
-3
type a value
-2020
Live values
  • Sum2
  • Difference8
  • Absolute difference8
xy
  • y = a + x

Formulas in this lab

  • Sum
    a+ba + b
  • Difference
    a−ba - b
  • Absolute difference
    ∣a−b∣|a - b|
Tip: Adding a slides every input up (a > 0) or down (a < 0); the slope stays 1.

Frequently asked questions

▶How do I add two integers with different signs?

Take the difference of their absolute values and keep the sign of the bigger one. For example, 5 + (-3) gives 2 because 5 is larger. The lab slides both a and b along the number line so you can watch the jump happen visually.

▶How do I use the integer number line lab?

Slide the two sliders for a and b. The lab will show the sum a + b and the difference a - b along with the jump arrows on the line. Try a = -7 and b = 4 to see how subtraction pulls you back toward zero.

▶Why is 100 - 150 a negative number in real life?

If you have Rs 100 in your pocket and a snack costs Rs 150, you are short by Rs 50, shown as -50. The number line in this lab is exactly how shopkeepers and bank passbooks record dues, with negatives for what you owe.

▶Adding a negative vs subtracting a positive: are they the same?

Yes. 8 + (-3) and 8 - 3 both give 5. Many students get confused by the two minus signs in 8 - (-3), which actually means 8 + 3 = 11. Slide b to negative values in the lab and watch the answer flip to see this clearly.