Download Solving Equations

Solving Equations
Inverse operations
INVERSE = Opposite
• If I am solving an equation using
inverses operations, I am solving it
using opposite signs.
• Example: addition and subtraction are
opposites.
• Multiplication and division are
opposites.
WHEN CAN I USE INVERSE?
• When I have the following, I can use
inverse operations:
• 9(a)=19
If there is no sign,
• A(9)=19
it means multiply.
• The opposite of multiply is divide, so
divide the 2 numbers to find the value of
the number.
When can I use inverse?
• N ÷ 9= 5
• The opposite of divide is multiply, so
you will find n by multiplying the two
numbers.
• You can not use the inverse in division if
the number comes before the letter like
in
9 ÷ n = 45.
When Can I Use Inverse?
• N-3= 9
• The opposite of subtract is add, so I will
add the 2 numbers to find N.
• With subtraction, I can only use inverse
if the letter comes first.
• I cannot do 3-n=2 using inverse.
When can I use inverse?
• 9+n=10 or n+9=10
• The opposite of add is subtract, so
subtract the smallest number from the
largest to find your answer.
Division
• If the number comes first in division, I
will divide to find my answer.
• Example 20÷n=5
• I will divide to find my answer.
Subtraction
• If the number comes first in subtraction,
I will subtract to find the answer.
• Example:
• 12-n=3
n=12-3
Try some using inverse!!!
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n-9=10 What is n?
16+n=19 What is n?
n÷5=9 What is n?
n(5)=45 What is n?
12(n)=3 What is n?
Some more
• Practice 21.2