Area of a Triangle

1
Area of a Triangle

• Section 8.4

2
Theorem
The area A of a triangle is
where b is the base and h is the altitude drawn
to that base.
3
Right Triangle Area Sides a, b Hypotenuse c

• Area is
• ½ ab
• ½ bc
• ½ ac
• None of these

4
a
h
b
5
Theorem
The area A of a triangle equals one-half the
product of two of its sides times the sine of its
included angle.
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(No Transcript)
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Theorem Herons Formula
The area A of a triangle with sides a, b, and c is
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Sides a, b, c in inches. What are the units for
triangle area?

• inches
• square inches
• cubic inches
• None of these

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10
Find the area of the triangle with sides a8
b10 c12

• 0 square units
• 25.67 square units
• 42.33 square units
• 39.69 square units
• 124.19 square units
• 72.47 square units
• 56.88 square units
• 98.12 square units
• None of these are close