7th Grade Math

Test PracticeTT

C 28. CHALLENGE To find the total number of polygon

diagonal

diagonals for any given polygon, you can use

the expression

n(n - 3)

_

2

, where n is the number

of sides of the polygon.

a. Determine the minimum value that n could be.

b. Make a table of four possible values of n. Then complete the table by

evaluating the expression for each value of n.

29. REASONING Write an algebraic expression with the variable x that has a
    value of 3 when evaluated.


30. CHALLENGE Name values of x and y so that the value of 5x + 3 is greater
    than the value of 2y + 14.


31. OPEN ENDED Write a real-world problem that can be represented by the
    expression 5x + 10.


32. E WRITE MATH Tell whether the statement below is sometimes, always,
    or never true. Justify your reasoning.
    The expressions x - 3 and y - 3 represent the same value.


33. Which expression could be used to find
    the cost of buying b books and m
    magazines?

School Book Fair Prices

Item Cost

Magazines $4.95

Paperback books $7.95

A. 7.95b + 4.95m C. 12.9(b + m)

B. 7.95b - 4.95m D. 12.9(bm)

34. Tonya has x quarters, y dimes, and
    z nickels in her pocket. Which of the
    following expressions gives the total
    amount of change she has in her pocket?
    F. $0.25x + $0.05y + $0.10z
    G. $0.25x + $0.10y + $0.05z
    H. $0.05x + $0.25y + $0.10z
    I. $0.10x + $0.05y + $0.25z


35. CAMPING The table shows the costs of different camping activities.
    Over the summer, Maura canoed 4 times and fished 3 times. Write
    and evaluate an expression that represents the total cost Maura
    spent canoeing and fishing.(Lesson 1B)


36. PARADES There were about 10^5 people at the parade. About how
    many people attended the parade?(Lesson 1A)

Lesson 1C Expressions 37

Camping Activity Costs

Activity Cost

Canoeing $8

Fishing $5

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