Subtraction Sentences Using Number Lines - Up to 20
š¦ Hop backward down the number line! We can use a number line to make subtracting up to 20 super visual and easy.
Concept
A number line is a straight line with numbers written in order. When we subtract, we hop **backward** down the line towards zero! šÆ **How to Subtract on a Number Line:** **Example: 15 - 4 = ?** 1. **Find your starting point:** Put your finger on the big number, 15. 2. **Look at the minus number:** You need to subtract 4. That means 4 hops backwards. 3. **Hop Backward!** Hop to the left 4 times: "14... 13... 12... 11". 4. **Find your landing spot:** You landed on 11! So, **15 - 4 = 11**. Number lines help you see the subtraction happening, instead of just trying to memorize it!
Try it
Let's do some backward hopping! **Instructions:** Imagine a number line stretching from 0 up to 20. Count your backward hops. **Problem 1: 18 - 3 = ?** * Start at 18. * Hop backward 3 times: "17, 16, 15". * Landing spot: ___ **Problem 2: 14 - 5 = ?** * Start at 14. * Hop backward 5 times. * Landing spot: ___ **Problem 3: 19 - 2 = ?** * Answer: ___ **Problem 4:** You start at 20 and take 6 hops backwards. Where do you land? * Math sentence: 20 - 6 = ___ * Landing spot: ___