DVMT 108 Testing Enhancement Workshop

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DVMT 108Testing Enhancement Workshop

• Department of Mathematics and Computer Science
• Coppin State University
• September 2009

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Outline

• Signed numbers
• Basic operations
• Evaluate signed number expressions
• Special equations
• Quadrants

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Addition and Subtraction

• Same sign
• Ex 13 4
• -1 -3 -4
• Keep sign and add the absolute values.
• Different signs
• Ex -1 20 19 19
• 11- 29 -18
• Give the sign of the number having the larger
  absolute value and subtract absolute values.

4
Multiplication and Division

• Same sign positive
• Ex -1 (-3) 3 3
• -18 (-3) 6
• Different signs negative
• Ex -1 (20) - 20

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Multiplication and Division

• Same sign positive
• Ex -1 (-3) 3 3
• -18 (-3) 6
• Different signs negative
• Ex -1 (20) - 20

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Multiplication and Division

• Same sign positive
• Ex -1 (-3) 3 3
• -18 (-3) 6
• Different signs negative
• Ex -1 (20) - 20

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• A 5)

Textbook Page 80 When dividing fractions,
multiplying by the reciprocal of the divisor.
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Select the lesser of two numbers

• 2 -2 2
• -2 -12 -1 2-2
• --2 -1 -2 -1 2 -2
• A2) --2 and --20
• --20 -20
• --20 is the lesser
• B6) -19 and -23
• -1919 -2323
• -19 is the lesser.

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Evaluate sighed number expressions

• A7) evaluate (-6x-3y)(-2a) given x -2, y3 and
  a-4.
• Substitute x, y and a by the given numbers.
• (-6x-3y)(-2a)
• -6(-2)-3(3)-2(-4)
• (12-9)(8)
• 3(8)
• 24
• Always use parenthesis around the negative
  numbers.

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Perform the indicated operations

• A8)

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The difference

• A4) After one round in a card game, your score
  was 44 points. After the second round, your score
  was -42 points. How many points did you lose in
  the second game?
• Gain / Lose-
• -42-44
• -(4442)-86

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The difference of signed numbers

• B9)The stock market gained 15 points on Tuesday
  and lost 11 points on Wednesday. Find the
  difference between these changes.
• 15-(-11)
• 1511
• 26

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Distributive Property

• -2(5) -10
• -2(5x) -2(5) (-2)x-10-2x
• A10) Use the distributive property to rewrite the
  expression.
• -8(3x) - 8(-5y)
• -8(3x) (-8)(-5y)
• -8(3x - 5y)

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Exponents

• Question (-2)2 -22?
• (-2)2 (-2)(-2) 4
• Answer NO.
• -22 -1(2 2) -1(4) -4
• (-2)3 (-2)(-2)(-2) -8

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Evaluate the polynomial

• A27)Evaluate 2x3 - 6x2 - x 10 for x -2.
• Substitute x by (-2).
• 2(-2)3 - 6(-2)2 - (-2) 10
• (use parentheses around the numbers)
• 2(-8) - 6(4) 2 10
• -16 - 24 12
• -40 12
• -28

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Equations

• A12)
• Solve 3x - 4x 7
• -x 7(combine like terms)
• x -7(divide both sides by
  -1)

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Special Equations

• A13) Solve 24(x - 2) 6(4x 3) - 66
• 24x - 48 24x 18 - 66
• 24x - 48 24x - 48
• -24x 48 -24x
  48
• 0 0
• True statement.
• Solution all the real numbers.

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Special Equations

• Solve -2(3y - 5) -6y 1
• -6y 10 -6y 1 (add 6y both
  sides)
• 10 1
• False statement.
• No solution.

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Quadrants