Page 33 - 新思维数学活动用书8 样章

2 Expressions, formulae and equations

12 A square has a side length of 7 cm.
y
A rectangle has a length of − cm and a width of 4 cm.
3
8
The square has the same perimeter as the rectangle.
Work out the value of y. Show all your working.

13 a Complete the workings to solve this equation.

x + 4 = 3
6
x + 4 = 3 × 6
x + 4 = 18
x =

b Solve these equations.

i x + 2 =−4 ii 3x − 1 = 7
7 2
14 Solve these equations.

a 4 y = 32 b 5 z −=
37
5 7

c 2(5n − 4) = 12 d 4    2 m − 3 = 20


3
15 Here is a secret code box.

8 11 8 3 7 4 5 2 9
Solve each equation below.
Use your answers to fill in the letters in the code box to find the

name of a Winter Olympic sport.

L 4(x − 5) = 8 G 2(2x + 3) + 5x = 24
H 2(x + 3) = 3x − 3 E 12 + 3(x + 4) = 36

O x −5 = 1 S 30 = 6(2x − 1)
6
I 5x + 3 − 2x − 1 = 17 B 2(x − 5) = 3(2x − 14)

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