Download Math 67 Unit 9 Quiz Expressions Study Guide

Math 6/7 Unit 9 Quiz: Expressions (Study Guide)
1. State whether the following conjecture is true or false. If false, provide a counterexample.
The difference of two different whole numbers is always less than both of the two
numbers.
_____The statement is false. A counterexample is the subtraction problem 8-1. The
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difference between 8 & 1 is 7. 7 is less than 8, but 7 is not less than one.
expr
essi
__________________________________________________________________________
on
belo
w
has been simplified. Justify each step.
2.
(6n • 7) • 4n
3. (4m • 3) • 2m
= (7 • 6n) • 4n____Commutative_______
= (3 • 4m) • 2m_____Commutative_____
= 7 • (6n • 4n)____Associative _________
= 3 • (4m • 2m)_____Associative________
= 7 • 24n2_______simplify_____________
= 3 • 8m2___________simplify____________
= (7 • 24) • n2___Associative__________
= 168n2_________simplify____________
= (3 • 8) • m2________Associative ________
= 24m2_____________simplify____________
*Use Distributive Property to rewrite each expression
4. -3(X – 4)
______-3x + 12__________________
5.
______
6. 7(4x – 5y)
______28x – 35y_______________
10. 7(4y – 5z) _____28y – 35z______________
7. -5(x + 4y)
_____-5x – 20y________________
11.
________________
8. (x + 4)(3) _______3x + 12_________
9. (7x – 6y)8 _____56x – 48y_____________
______
___
*Identify the terms, like terms, coefficients, and constants in each expression.
12. 5a + 7a + 8
Terms: ____5a, 7a, 8_____________
Like Terms: ____5a, 7a_______________
Coefficients: _____5, 7_________________
Constants: ______8_________________
13. 9 – 5x + 4
Terms: ____9, -5x, 4____________
Like Terms: _____9, 4___________
Coefficients: _____-5_________
Constants: ______9, 4_____________
*Write each expression in simplest form
14. n + 6n + 8 + 12 – n
__________6n + 20____________
15. 8 – n + 4n + 7n
___________10n + 8__________________
16. 8 + 5n – 6 + 9
__________5n + 11__________________
17. -4x + 9 – 10x -15
__________-14x - 6_______________
*Write an expression for the perimeter of the figure below.
18.
P: 15n + 12
6
6
15n
19.
7b
P: 28a + 7b + 15
14a
14a
15
*Add
20. 7(x + 5) + (9x + 3)
16x + 38
21. 12(2x – 12) + (8x – 10)
32x - 154
22. (x – 15) + (4x – 8)
5x - 23
23. 8(x + 12) + (-6x + 15)
2x + 111
24. (-5x + 9) + 8(2x – 10) 11x - 71
25. (12x – 8) + 4(8x – 7)
44x - 36