Understanding Subtraction: Minus Numbers in Math Explained

  • Thread starter Thread starter runescapedude
  • Start date Start date
Click For Summary

Homework Help Overview

The discussion revolves around understanding subtraction, particularly when subtracting larger numbers from smaller ones. Participants are exploring the concept of negative numbers and their representation on a number line.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants are attempting to understand the mechanics of subtraction involving negative results and the use of a number line. Questions about the meaning of terms like "number line" and "coordinate" are raised, along with confusion regarding practical methods for performing subtraction.

Discussion Status

Some participants have offered guidance on using a number line to visualize subtraction, while others express confusion about the concepts and methods being discussed. There is a recognition of the need for clearer explanations, especially for younger students.

Contextual Notes

Participants mention challenges related to learning environments, such as fast-paced teaching and the use of physical counting methods, which may not be effective for all students. There is also a reference to classroom dynamics and personal experiences with understanding math concepts.

runescapedude
Messages
3
Reaction score
0
My teacher said when we take away a number bigger than a nuther number we have to do a minus number. 5-7=something


I don't get what she means.
 
Physics news on Phys.org
Think of the numbers paired to points on a number line. Increasing to the right are the positive numbers; increasing to the left are the NEGATIVE numbers. directly at the "start" of the positive numbers and the negative numbers is the one point which they share. That is the number ZERO.

You can perform simple arithmetic using this number line. If you begin with 5, and then SUBTRACT 7, this means you start at 5 and then move 7 units to the left. Which point (coordinate) on the number line does this take you? You should have located the number, NEGATIVE 2, which you would write as: -2
Notice also that this is 2 units to the left side of ZERO.
 
symbilpoint i don't get what you mean like what's a number line and coordinate means what?ok so i put -2 <negetive 2> so 5-7=-2 ok but there is a nuther 1 I have to do. number 2 says find 3-7+2


I don't get it becous when I use my fingers I don't no what to do when all put all the fingers downe. there's not enuff fingers if I use my other hand to put them up so can you help if you tell me how to use the fingers if their is a minus number like if I put my other fingers up or what.

Thx!
 
Runescapedude, do not use your fingers! Use a number line. You can take yourself through the calculation and see where the expression, 3-7+2, will be on the number line.

Young students in grade 1 usually learn to add and subtract whole numbers both on a number line and on their fingers. At that grade level, the number line starts at zero, and counts upward to the right. Those students in grade 1 only use whole numbers, and they are only the positive numbers.

Now that you are learning to subtract larger numbers from smaller numbers, you need to extend the number line toward the left of zero to use the negative numbers.
 
runescapedude said:
My teacher said when we take away a number bigger than a nuther number we have to do a minus number. 5-7=something


I don't get what she means.

What if you had $25 in your checking account, but you wrote a check for $30? (Banks of course don't like you to do this.)
 
I don't get what you mean like starts at zero and counts upward to the right. I am in yeer 3 but no 1 like's the teacher becous she puts me on deetenshen... She put on the bord this thing with lines but other lines 2 with ulot of number's and she torks fast and torked to fast for me to rite but evriwon gets it beter.


I don't get $ and what is the check thing mean. I have a bank with mor dolers than my frend Jack becous he has 20 dolers and I have mor. Do you have mor.
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 9 ·
Replies
9
Views
2K
Replies
4
Views
3K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
10
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K