"<span>Triangle ABC is similar to triangle ABD 3. Angle ABC = Angle BAD and Angle BAC = Angle ABD" is the one step among the following choices given in the question that has the error. The correct option among all the options that are given in the question is the third option or option "3". I hope the answer has helped you.</span>
angles in a triangle need to equal 180 degrees
so x = 180 - 47 - 58
x = 180-105
x= 75 degrees
Hi!
When a number has lines on the outside of it like that, it means that it's the distance from 0. It's known as the absolute value.
|−8.6|'s distance from 0 is 8.6.
The answer is d 8.6
Hope this helps! :)
-Peredhel
Let the equal sides of the isosceles Δ ABC be x.
Given that the perimeter of Δ ABC = 50m.
Therefore, 2x + AC = 50 --- (1)
It is also given that the perimeter of Δ ABD = 40m.
Therefore, x + BD + AD = 40
BD is the median of the Δ ABC. Therefore, D is the midpoint of AC.
So AD = CD.
Or, AD =
AC
Therefore, 
Multiply both sides by 2.
2x + 2BD + AC = 80
From (1), 2x + AC = 50.
Therefore, 2BD + 50 = 80
2BD = 80 - 50
2BD = 30
BD = 15m.