Question

Logan is a land surveyor. He wants to determine d, the distance across a lake that cannot be directly measured. He draws this diagram to help him.
A right triangle with side length 7 kilometers, d, and hypotenuse of 9 kilometers.

What is the approximate distance across the lake, to the nearest tenth of a kilometer?
5.7 km
6.3 km
11.4 km
16.0 km

Answer 1

Answer:

The first option     (5.7km)

Step-by-step explanation:

Since we have a right angle triangle and we know two of its sides we can easily find out the thirds side (the value of d) by using the Pathagoras Theorem. In our case 7 and d are our legs and the hypotenuse is equal to 9, so...

(Based on the Pathagoras Theorem)

$c^{2} = a^{2} + b^{2}$

$9^{2} = 7^{2} + d^{2}$

$d^{2} = 9^{2} - 7^{2} \\d^{2} = 81 - 49\\d^{2} = 32\\d = \sqrt{32}$

d ≈ 5.7km

There for aproximate distance across the lake is equal to 5.7km

Answer 2

Answer:

A

Step-by-step explanation: