Question

I need help with this question ( see image). Please show workings.​

Answer 1

14) (C) 8√2 km

15) (C) 225°

Exercise 15.17 (D) 8.7 km

Explanation:

14)

d² = 8² + 8² = 64 + 64 = 128

d = √128 = 8√2 km

15) 180° + 45° = 225°

Exercise 15.17

QR² = 10² - 5² = 100 - 25 = 75

QR = √75 = 5√3 = 8.7 km

Answer 2

Kofi, the building and the tree form an isosceles right triangle KTB.

Refer to picture

15.15

The distance KB is the hypotenuse and its length is:

• KB = √8² + 8² = √64 + 64 = √128 = 8√2

Correct choice is C

15.16

The angles at vertices K and B equal to 45° as opposite sides are equal.

TB is a vertical line which makes angle 180°.

Add 45° to get a required bearing:

• 180°+ 45° = 225°

Correct choice is C

15.17

P, Q and R form a right triangle with PR as hypotenuse.

RQ is the missing leg and its length is:

• RQ = √PR² - PQ² = √10² - 5² = √100-25 = √75 = 8.7 (rounded)

Correct choice is D