Core Connections Integrated II, 2015
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Core Connections Integrated II, 2015 View details
1. Section 7.1
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Exercise 32 Page 383

If you draw the height of the triangle, we create two congruent right triangles.

About 62.34 square units.

Practice makes perfect

An equilateral triangle is a triangle with three congruent sides and three congruent angles of 60^(∘). Let's draw this triangle.

The area of a triangle is the product of its base and height divided by 2. Therefore, let's draw the height from the top angle, dividing the equilateral triangle into two congruent right triangles.
By substituting θ= 60^(∘), opposite= x, and adjacent= 6 in the tangent ratio, we can solve for x.
tan θ = opposite/adjacent
tan 60 = x/6
Solve for x
6tan 60 = x
x= 6tan 60
x= 10.39230...
x≈ 10.39
The area of a triangle can be calculated by multiplying its base and height and dividing the product by 2. We now know that the height is about 10.39 units long. With this information, we can find the triangle's area.
A=1/2bh
A=1/2( 12)( 10.39)
Simplify right-hand side
A=12* 10.39/2
A=6* 10.39
A=62.34
The area is about 62.34 square units.