Use trigonometry to find the perpendicular height of a triangle

Use trigonometry to find the perpendicular height of a triangle

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Lesson details

Key learning points

  1. In this lesson, we will identify the perpendicular height of triangles, use trigonometry to find the perpendicular height and apply this to find the area of a triangle.

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3 Questions

Q1.
A ladder leans against a wall. It is 3m away from the wall at an angle of 60 degrees. What is the length of the ladder?
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x = 1.5 m
x = 4.70 m
Correct answer: x = 6 m
Q2.
2. A man stands exactly 8m from a lamppost. He looks to the top of the lamppost, as shown. What is the height of the lamppost? Answer to 1 dp
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11.9 m
13.4 m
5.4 m
Correct answer: 7.2 m
Q3.
Find the perpendicular height of this parallelogram ( to 1 dp)
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10 cm
Correct answer: 10.6 cm
3.5 cm
3.54 cm

3 Questions

Q1.
If b is the base, identify the perpendicular height of this triangle.
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s
Correct answer: t
u
Q2.
Find the perpendicular height of the triangle.
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0.0333… cm
1 cm
Correct answer: 7.5 cm
Q3.
Find the perpendicular height of the triangle. Give your answer to one decimal place.
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5.9 cm
Correct answer: 7.2 cm
8 cm

Lesson appears in

UnitMaths / Trigonometry 2