Question

The diagram represents a set of beams that form part of a bridge support. Label AB and BD with their lengths, rounded to the nearest foot.Enter the correct answers in the boxes.

Answer 1

BD = 12 ft

AB is 15 ft

Step-by-step explanation:

The two triangles are right angled, so we would apply pythagoras' thorem:

Hypotenuse² = opposite² + adjacent²

First we would go for the second triangle as two of the sides are given.

Hypotenuse = 14, adjacent = 7, opposite =BD

14² = BD² + 7²

196 = BD² + 49

BD² = 196 - 49 = 147

BD = √147 = 12.12 ft

To the nearest foot, BD = 12 ft

1st triangle:

Hypotenuse = AB,

opposite = BD = √147

adjacent = 9 ft

AB² = (√147)² + 9²

AB² = 147 + 81 = 228

AB = √228 = 15.0997

To the nearest foot, AB is 15 ft