Page 36 - 新思维数学活动用书8 样章

2.6 Inequalities

8 Copy and complete these equivalent inequalities.
a x > 4 is equivalent to 2x > b x < 9 is equivalent to x < 63

c y ⩾ 1 is equivalent to y + 9 ⩾ d y ⩽ 1 is equivalent to y − 5 ⩽
9 This is part of Lori’s homework.

Question
Use the inequality –3 < x < 3 to write
i the smallest integer x could be

ii the largest integer x could be
iii a list of the integer values x could be.
Answer
i smallest integer is –3
ii largest integer is 3

iii x could be –3, –2, –1, 0, 1, 2, 3

Explain the mistakes Lori has made and write the correct solutions.
Make sure you correct all of Lori’s mistakes.
10 For each inequality, write
i the smallest integer y could be

ii the largest integer y could be
iii a list of the integer values y could be.
a 32 < y < 38 b 24 < y ⩽ 27

c 40 ⩽ y < 44 d −12 ⩽ y ⩽ −9
11 Write true (T) or false (F) for each statement.
The first one is done for you.
a 8 > y > 2 means the same as 2 < y < 8 T

b 10 > y ⩾ 0 means the same as 0 ⩽ y < 10
c 1 ⩾ y ⩾ −4 means the same as 1 ⩽ y ⩽ −4
d 3 ⩾ y > −3 means the same as −3 ⩽ y < 3

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