Page 28 - 新思维数学活动用书7 样章

2.3 Collecting like terms

2 Look at these statements. Three of the statements are true and three of
the statements are false.
Write ‘true’ or ‘false’ for each statement. If the statement is false, write the
correct statement.
a b + 2b = 3b b 4d + 2d = 5d

c 6f + 4f = 11f d c + c + c = 3c
e h + 3h + 5h = 8h f 7v + 2v + v = 10v
3 Each of these expressions simplifies to 3s or 5s.
For each rectangle A to E, write down whether it simplifies to: Tip

i 3s or ii 5s. Think of s as a
The first one has been done for you: A and ii.
strawberry. For

9s – 4s 5s – 2s 8s – 5s 6s – s 10s – 5s example, for A,
you start with
A B C D E nine, you eat four,

4 Look at these statements. Three of the statements are true and three of so you have five
the statements are false. strawberries left.
Write ‘true’ or ‘false’ for each statement. If the statement is false, write the

correct statement.
a 7b − 2b = 3b b 4d − 2d = 2d
c 6f − f = 6 d 8c − 2c − 3c = 3c

e 9h − h − h = 7h f 10v − 6v − v = 4v
5 Look at these expressions. Some of the expressions can be simplified and Tip
some cannot be simplified. Copy the expressions. You can simplify
If the expression can be simplified, write a tick and work out the only when

simplified answer. the letters are
If the expression cannot be simplified, write a cross. the same.
For example: 4m + 2m ✓ 6m
2a + 3b ✗

a 5p + p b 6p + 2 c 5n − 2w d 8u − u

Practice
6 Pedro has striped, checked and spotted bricks.
The length of a striped brick is x.

The length of a checked brick is y. x y z
The length of a spotted brick is z.

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