Answer to Homework

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Warm ups - PEMDAS
62  42
 23
2(3  2)
[6  (2  4)2]3
2
3-2 Solving Equations
with Multiplication and
Division
Objective: To solve
equations using
multiplication and division
Examples 1 – 3 (watch & listen)
5x = 15
5
5
x=3
-4r = -28
3w = -11
3
3
w = -11
3
Examples 4 – 6 (do with me)
1.7b  39.1
x
11 
5
c
 14
8
Example 7 (with a partner)
3
x  5
4
2
n  10
5
Examples 8 - 9
Six times a number is
-96. Find the number.
6n = -96
6
6
n = -16
Negative twelve times a
number is -156. Find
the number.
TOO (Try on your own)
1)
-3x = -24
2)
f
 63
14
3)
2
4
x
5
7
Homework
Pg. 153 # 15 – 31 odd
Check your answers in the back
of the book.
Objective
The student will be able to:
solve equations using multiplication and
division.
1) Solve.
-5t = 60
To get the variable by itself, which
number needs to be moved?
-5
To move the -5, you have to do the
opposite operation. What
operation will we use?
division
1) Solve -5t = 60
1.
2.
3.
4.
Draw “the river” to
separate the equation
into 2 sides
Divide both sides by -5
Simplify
Check your answer
-5 -5
t = -12
-5(-12) = 60
4) Solve
x
 12
4
You don’t like fractions? Let’s get rid of
them! 
“Clear the fraction”
by multiplying both sides of the
equation by the denominator.
1.
2.
3.
4.
x
 12
4) Solve
4
Draw “the river”
x
Clear the fraction –
4 ·  12 · 4
multiply both sides by 4
4
Simplify
Check your answer
x = -48
48
 12
4
Math Lab


Homework
Please finish worksheets from yesterday


Why did the ant run across the cracker box?
What did the Spanish Farmer say to his chicken?
Try these on your own...
x=3
7
4w = 16
y=8
-2
2x = 12
3
-2z = -12
3x = 9
-4
The answers...
x = 21
w= 4
y = -16
x = 18
z=6
x = -12
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