10-5 Trigonometry and Area
To find areas of regular polygons and
triangles using trigonometry
Using trigonometric functions, students will calculate the areas
of triangles and regular polygons accurately, efficiently, and to a
degree of precision appropriate to the situation.
• The following questions are designed to help you
determine how well you understood today’s lesson.
• Please take time to ask questions if you miss one
and don’t know why!
• Record the number you get right on your portfolio
1. Find the area of the regular polygon. Give the answer to the nearest tenth.
pentagon with a side of 6 ft
2. Find the area of the regular polygon. Give the answer to the nearest tenth.
hexagon with a side of 6 in.
3. Find the area of the regular polygon. Give the answer to the nearest tenth.
square with a radius of 13 ft
4. A park in a subdivision is triangular-shaped. Two adjacent
sides of the park are 581 feet and 540 feet. The angle
between the sides is 83 . To the nearest unit, find the area
of the park in square yards.
5. Find the area of the triangle. Give the answer to the
nearest tenth. The drawing may not be to scale.
Be sure to RATE your understanding of the
lesson 4-3-2-1-0 after you finish it AND give me
one complete sentence as to why you rated
yourself that way then summarize what the
lesson was about in a sentence or two.