How to solve Directed numbers.
Direct numbers are positive and negative numbers, they can be represented on a number line, so in this post i will talk about how to add, subtract, multiply and divide direct numbers.
Addition and Subtraction of Direct Numbers.
Now if two numbers of opposite signs that are added together, at the end of calculation the bigger number sign will prevail, i.e -2+5=+3, 5 is the bigger number and its sign was positive so at the end your answer must end up positive.Any sign at the left hand side (LHS) of a number belongs to that number that is, - 3+5-6
3 has a negative sign, 5 has the positive sign and 6 has a negative sign.
Now lets define positive and negative numbers in terms of money, lets say a positive number is the amount you have currently, while negative numbers are the amount you are owing.
Lets solve some examples
1. - 5+7= you have 7 and you pay the 5 you are owing, how much do you have left, so -5+7=2.
2. - 4 - 3= now you are owing 4,and you still went back to owe another 3,so how much are you owing in total, so -4-3=-7, where the negative sign means you are still owing.
3. 1-2+5-6=
Now let us group the positive numbers from the negative, i.e collect like terms.
1+5-2-6
1+5=6
-2-6=-8
therefore we have 6-8,which means you have 6 and you owed 8,if you pay back 6 how much is left, so you are still owing 2,which means - 2.
4. - 8+5-6+1-2=
-8-6-2=-16
5+1=6
-16+6=-10.
I hope you now understand the basics on directed numbers.
Multiplication and Division of Directed Numbers.
We have a rule that+×+=+
- × += -
+ × - = -
- × - = +
+ ÷ += +
+ ÷ - = -
- ÷ + = +
- ÷ - = +.
So let us solve some examples.
1. - 2-(-5)=
Solution
-2[- × -]5 = - 2+5=3.
2. 3-(2)(-3)=
solution
3- [+ × -](2×3) =3-6= - 3.
3. - 4 × 3/-6
Solution.
[- × +](4×3)/-6
- × + = -
-12/-6= [- ÷ -](12/6)
- ÷ - =+
+2.
You can try these out :
1. 6-4+7-1+2-3 =?
2. - 1-5-6-7-2+4+5+2-3 =?
3. 1(-3) × 2(-3)/-8
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