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Answer:
B. 5√3 is your answer.
Step-by-step explanation:
This is an equilateral triangle, which means that all external sides (that make up the triangle) have the same measurement.
This means that line segment AC = 10.
Solve for the measurement of line segment AB. Line Segment AB is 1/2 of AC, making it: 10/2 = 5
Line AB = 5
Line AD = 10
This is a 1, √3, 2 triangle, in which:
1 = 5
2 = 10
Solve for √3. Multiply √3 with the 1:
5 x √3 = 5√3
B. 5√3 is your answer.
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Answer; B
If the triangle is equilateral...then all sides are equal and the interior angles are all 60°
If line BD bisects <D...then the angle ADB = 30°(60° ÷ 2)
Then apply the trigonometry formula
where we state that....
Cos theta = BD/10
;Cos 30° = BD/10
; 10 Cos 30° = BD
Length BD = 10(square root of 3/2)
Which then gives us..BD = 5(square root of 3)