Transcript i) Negative Coefficient Equations

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Is this a “positive 5” or “plus 5”?
+5 – 2x = 14
positive 5 is the same as a plus 5
BOTH
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HINT: If you don’t see a negative
or positive sign in front of a
number it is always positive.
+5
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Is this a “negative 7x” or “minus 7x”?
2 – 7x = 10
negative 7x is the same as a minus 7x
BOTH
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HINT: The sign in front of the
number BELONGS TO THE NUMBER!
–7
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What’s the coefficient?
The coefficient is the
number before the variable.
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Name the Coefficient
3 +4=3
3x
5 – 77x = 2
8 –1x = 10
What does – represent?
It represents -1.
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Name the Coefficient
--1x + 8 = 5
8 – 66x = 4
4 – 1x = 10
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1) GOAL: Get the variable on one side
of the equation.
2) You always perform the same operation to
both sides of an equation.
3) To undo an operation you perform its
opposite operation to both sides of the
equation.
4) It is easier if you undo addition or
subtraction before you undo multiplication
or division.
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I will show you how to solve this problem 2 different ways.
7  x  13
7  x  13
x  x
7  x  13
13
 13
7  x  13
7
7
1x  6
1x  6
1
1
x  6
6  x
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Solve each equation. WATCH THE SIGNS!
1) 5  3x  26
5
5
3x  21
3  3
x  7
2)  4y  9  39
9  9
4y  48
4  4
y  12
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Solve each equation. WATCH THE SIGNS!
3) 7  10  x
10  10
3  1x
1  1
3x
4) 24  n  30
24
 24
1n  6
1n  6
1 1
n  6
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Solve each equation. WATCH THE SIGNS!
5) 3y  7  5y  19
6) 8  2k  3k  13
2y  7  19
7  7
2y  12
2  2
y  6
8  k  13
8
8
1k  5
1  1
k  5
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The
End!
Take out your study guide!
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#17
3 - 2x = 11
-3
-3
-__
2x =__
8
-2 -2
x = -4
1)Get the variable alone, even
if the coefficient is negative.
2)Subtract 3 from both sides.
3) +3 and -3 cancel out
4) Divide both sides by - 2
5) -2 divided by –2 cancel out
6) Show your check.
3 - 2(-4) = 11
3 + 8 = 11
11 = 11 7) Finish your check.
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