PRE ALGEBRA - INTEGERS
ADDITION, SUBTRACTION, DIVIDING, MULTIPLICATION
You should have a good understanding of integers - (numbers) and be able to add, subtract, multiply,
and divide them.
Adding and Substracting Integers
When first learning, the number line can be a good reference, for adding and subtracting integers.
You can add and subtract using the number line as shown.
Start at 0 when using the number line for adding or subtracting
Positive integers are to the right of 0, and negative integers are to the left of 0, on the number line.
Solve this equation with the number line:
-3 + (-2) = ?
-------------------------------------------------------------------------------
-5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10
As the math problem is -3 + (-2),
At 0, count 3 to the left, then add 2 additional, for -3 + (-2) = -5
Multiplying and Dividing with Integers
You need to know:
negative (-) x (-) is positive (+)
negative (-) x (+) is negative (-)
Therefore:
4 x (-4) = -16
(-4) x (-4) = 16
If the result is negative -, then place in front of the number as shown, -16.
If the result is positive +, you don't place + in front of the number, 16.
ALSO:
When solving equations, you might see x or . or just ()() for multiplication problems.
(5)(5), (5)x(5), (5).(5) are all ways to show multiplying
INTEGERS PRACTICE SOLVING PROBLEMS
Addition:
FYI:
For addition: when signs are the same, just add the numbers and give the result the common sign
For addition: when signs are not the same, just subtract the numbers and give the sign from the larger value
SOLVE THE PROBLEMS
(-8) + (-13) =
5 + (-12) + 1 =
18 + (-12) + (-6) =
9 + (-13) + 3 =
ANSWERS
8 + 13, as both numbers have the negative sign, add the numbers, then add the negative sign =
Answer
-21
5 + (-12) + 1 =
5 + 1 + (-12) =
6 from 12, is 6, add the sign of the larger number -12 - which is negative
6 + (-12) = -6 Answer -6
18 + (-12) + (-6) =
add the negative signs together, -18
18 + (-18) = 0, positive 18 from a negative 18 equals 0= Answer
0
9 + (-13) + 3 =
add the positive signs together
9 + 3 is 12,
12 + (-13) = then subtract 12 from 13, and add the sign of the larger value, which is a negative sign,
Answer is -1
Subtraction
FYI:
For subtraction: when subtracting we add the opposite
For subtraction; when there are two negatives they become a positive
SOLVE THE PROBLEMS
(-14) - (-13) =
(-6) - 19 =
(-4) - (-15) =
ANSWERS
(-14) - (-13) = as there are two negatives we change them to a positive
(-14) + 13 = we now subtract the two integers, 14 minus 13 = 1
Then we add the sign of the larger value which is 14 with the negative sign
Answer is -1
(-6) - 19 =
(-6) + (-19) = we add the opposite, so - 19 becomes + (-19)
(-6) + (-19) = now we add the integers 6 + 19, and give the common sign which is negative = -25,
Answer -25
(-4) - (-15) = as there are two negatives we change them to a positive sign
(-4) + 15 = we now subtract the two integers, 4 minus 15 is 11
Then we add the sign of the larger value which is 15
Answer is 11
Add and Subtract, Multiply and Dividing
FYI:
For multiplying: negative x negative signs equals positive sign
For multiplying: negative x positive signs equals negative sign
For Dividing: the same rules apply for dividing as multiplying
SOLVE THE PROBLEMS
-3 + 7 + 4 -9 -2 -5 =
16 - (-4) -7 = 13
(7) (-3) =
(6) (15) =
(8) (-5) =
(-72) divided by (-9) =
21 divided by 7 =
ANSWERS
FYI
Complete the problem per the order of operations, that being, left to right for solving, and
Assuming your problem has any of these, complete in the order of :
What's in brackets, exponents first, then, multiply, divide, then addition and subtraction
-3 + 7 + 4 -9 -2 -5 =
complete the problem from left to right,
7 + 4 + (-3) + (-9) + (-2) + (-5) =
complete what's in brackets first
(-3) + (-9) + (-2) + (-5) + 7 + 4 = now add the total of your negative sign integers
(-19) + 11 = and minus 19 from 11 and give the sign from the larger value which is 19 negative
Answer: -8
16 - (-4) - 7 = because there are two negative we change them to a positive sign 16 + 4,
16 + 4 + (-7) = then change the minus to the opposite sign + (-7)
20 + (-7) = now we minus the two integers, 20 minus 7 is 13
13 and give the sign from the larger value which is 20 positive
Answer is 13
(7) (-3) = multiply 7 x 3 and give the negative sign because there is a negative and a positive sign
Answer is -21
(6) (5) = multiply the two integers and give a positive sign because both have positive signs
Answer is 30
(8) (-5) = multiply the two integers and give a negative sign because there is a negative and a positive sign
Answer is -40
(-72) divided by (-9) = divide 9 by 72 the answer is 8, now add the positive sign because 8 x -9 equals -72
Answer 8
21 divided by 7 = divide 7 by 21, for 3
Answer is 3
ALGEBRA - BECAUSE IT'S FUN TO LEARN
NEXT - Pre Algebra - Exponents
PREVIOUS - Pre Algebra - Number Line Integers
You Might Like:
Learn Spanish, Free
Learn Android Game Dev, Free
For addition: when signs are not the same, just subtract the numbers and give the sign from the larger value
For subtraction; when there are two negatives they become a positive
For multiplying: negative x positive signs equals negative sign
For Dividing: the same rules apply for dividing as multiplying
Complete the problem per the order of operations, that being, left to right for solving, and
Assuming your problem has any of these, complete in the order of :
What's in brackets, exponents first, then, multiply, divide, then addition and subtraction