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Solutions to the exercises

Exercise 1
a

P R = 18 and Q P = Q R = 34

b

Q P R = Q R P 69 ° and P Q R 43 ° .

c

First draw rectangle D B F H with D B = H F = ( 72 ) 8,5 and D H = B F = 6 cm.
Next draw point Q in such a way that B Q = 1 and point S in such a way that F S = 1 4 H F .
Now you can draw the pentagon D B Q S H .
This pentagon has two angles of 90 ° , one angle of 157 ° and an angle of 117 ° .

Exercise 2
a

T S = 18

b

B C and P Q are parallel and B P = C Q .
B P = C Q = 27 , B C = 6 and P Q = 3 cm.

c

To be able to draw this figure it is smart to first calculate the height of the trapezium. That height is 18 - 1,5 2 = 15,75 4,0 cm.
The trapezium has two angles of approximately 69 ° and two angles of approximately 111 ° .

Exercise 3
  • B C = 3 11 6 = 18 11

  • E G = 1700 and E F = 3 4 1700 .

Exercise 4
a

A E = D E = B F = C F = 50

b

A B F 65 ° and B C F 68 ° .

c

The width of the loft floor is 2 5 8 = 3,2 m.
The length of the loft floor is 6 + 2 2 5 3 = 8,4 m.
Therefore the area of the floor is 3,2 8,4 = 26,88 m2.

Exercise 5
a

Besides you see the (right) trapezium.
The edge denoted by 83,2 m has an exact length of 45 2 + 70 2 = 6925 .
The longest edge of the trapezium is 6925 + 6,5 2 = 6967,25 83,5 m.

b

Besides two right angles there is an angle of approximately 86 ° and an angle of approximately 94 ° .

Exercise 6
a

When h is the height of the tree, then 6 1000 h = 2 cm.
So h = 2000 6 333,3 cm. Therefore it is only a small tree of approximately 3,33 m.

b

When a is the distance to the Statue of Liberty: 6 a 9300 = 2 . This means a = 27900 cm, that is 279 m.

Exercise 7

( E Q ) ( A Q ) = ( E P ) ( A C ) = ( E P ) ( E Q ) = ( E F ) ( G F ) = 2 8 .
Take A Q = x , then E Q = x - 8 . So x - 8 x = 2 8 . This gives A Q = x = 10 2 3 .

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