Question

Which of the following would similar triangles and trigonometry be useful for measuring?

A. The length of a table
B. The width of a wide river
C. The length of a car
D. The width of the classroom

Answer 1

"The width of a wide river" is the one among the following choices given in the question for which similar triangles and trigonometry would be useful for measuring. The correct option among all the options that are given in the question is the second option or option "B". I hope that the answer has helped you.

Answer 2

The correct answer is:

B) The width of a wide river .

Explanation:

We can use trigonometric ratios to find the distance across a river, so long as we know the base of the triangle formed and one of the angles. For example:

"A farmer needs to find the width of a river that flows through his pasture. He places a stake (Stake 1) on one side of the river across from a tree stump. He then places a second stake 50 yards to the right of the first (Stake 2). The angle formed by the line from Stake 1 to Stake 2 and the line from Stake 2 to the tree stump is 72º. Find the width of the river to the nearest yard. "

After we draw the diagram, we see that we have the side adjacent to the 72° angle and are looking for the side opposite this angle. Opposite/adjacent is the ratio for tangent; we get the equation

tan 72 = x/50

Multiply both sides by 50:

50 tan 72 = (x/50)* 50

50 tan 72 = x

153.88 = x

154 ≈ x