Breaking down Equations one step - Yr9AMM

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Breaking down Equations – 0ne step
When there is an unknown letter, we would want to solve it or basically get a
value for this letter. Another word used to call this letter is a pronumeral.
Hence, you may see such statements in textbooks which says, ‘solve the
unknown’ or ‘solve for the pronumeral’.
The letter or pronumeral would indicate that we would like to find the value of
something that we do not know.
An example for this maybe, 2 dvds cost $21.00, so how much does one dvd
cost?
This can be represented as 2y= 21.50, y would represent the cost of a dvd, so 1
dvd would cost 21.50 divided 2, which would be $10.50.
In solving equations, remember, the opposite operations
Opposite operation
+
x
÷
add, plus
minus, subtract, take away
times, multiply,product
divide, over, quotient
-, minus
+, plus
÷, divide
x, times
In solving equations, what we are doing when using opposite operations is
simply to balance the equation so that we do not change the equation, what we
do to one side of the equal sign, we need to do the same to the other.
One step Equation
2y = 10, meaning 2 x y
Opposite operation
÷ or written as __
2 x y = 10
2
2
y=5
t + 7 = 12
t + 7 -7 = 12 -7
t= 5
opposite of +7 is -7
-
r =4
opposite of divide 3 is X3, so
3
3 X r = 4 X 3 , so r = 12
3
Solve for the pronumeral:
Opposite operation:
3t = 15
t = __________________
2g = 4
g = ___________________
r=6
2
r = ___________________
j – 5 = 11
j = ___________________
y = 10
3
y = ___________________
g+5=9
g = ___________________
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