1
a

2 x + 7 = 2 3 x + 7 = 3 x = 4

b

2 7 x = 2 4 7 x = 4 x = 4 7

c

2 x = 2 6 x = 6 x = 6

d

2 1 x = 2 3 1 x = 3 x = 1 3

2
a

3 x = 3 1 x = 1

b

3 x 5 = 3 1 x 5 = 1 x = 4

c

3 5 x = 1 3 2 = 3 2 5 x = 2 x = 2 5

d

3 5 2 x = 1 3 4 = 3 4 5 2 x = 4 2 x = 9 x = 4 1 2

e

5 1 2 x = 25 5 1 2 x = 5 2 1 2 x = 2 x = 4

f

5 3 x + 1 = 100 500 = 1 5 5 3 x + 1 = 5 1 3 x + 1 = 1 3 x = 2 x = 2 3

g

6 x 2 x = ( 6 2 ) x = 3 x = 9 3 x = 3 2 x = 2

h

3 x 1,5 x = ( 3 1,5 ) x = 2 x = 2 8 = 1 4 = 2 2 x = 2

3
a

-

b

x 0,333

c

f ( 1 3 ) = 4 1 3 = ( 2 2 ) 1 3 = 2 2 3 ; g ( 1 3 ) = 2 1 3 + 1 = 2 2 3 ; dus ze zijn exact gelijk

4
a

-

b

( 1,4 )

c

2 x + 3 = ( 2 2 ) x = 2 2 x x + 3 = 2 x 3 x = 3 x = 1 ; y = ( 1 4 ) 1 = 4

d

Kijk naar de grafieken: dat is links van het snijpunt, dus x < 1

5
a

3 2 x 1 = 1 3 2 x = 3 2 x 2 x 1 = 2 x 4 x = 1 x = 1 4

b

2 3 2 x = ( 2 2 ) x + 1 2 x 3 = 2 2 x 2 x 3 = 2 x 2 3 x = 1 x = 1 3

6
a

-

b

Ongeveer ( 3,3 ; 6,2 )

c

3 1 ( 3 2 ) x 2 = ( 3 1 2 ) x 3 1 3 2 x 4 = 3 1 2 x 3 2 x 5 = 3 1 2 x 2 x 5 = 1 2 x 3 2 x = 5 x = 10 3 ; invullen: y = 3 5 3 , dus het snijpunt is ( 10 3 ,3 5 3 )

d

Kijk naar de grafieken: dat is rechts van het snijpunt, dus x 10 3

7
a

40 minuten is 2 3 uur

b

g 50 60 = g 5 6 = 2 g = 2 6 5 2,297

c

Invullen: ( 7 2 1 2 ) 2 5 = ( 7 5 2 ) 2 5 = 7 1 = 7

d

7 2 5

8

x = 2 5 4 2,378

z = 2 1 1,4 = 2 5 7 1,641

a = 2 1 0,3 = 2 10 3 0,099

b = 5 3 5 0,381

c = 1 3 5 = 1

kan niet

p 7 3 = 4 p = 4 3 7 1,811

q 1,2 = 20 q = 20 1 1,2 = 20 5 6 12,139

9
a

g 10 = 1 2 g = ( 1 2 ) 1 10 = 2 1 10 = 2 0,1 0,933

b

g 12 = ( 2 0,1 ) 12 = 2 1,2 0,435 , dus 56,5 % is verloren gegaan

c

100 2 0,1 t = 75 , met de GR geeft t 4,15 , dus na 4 à 5 dagen