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△ACE, B is the midpoint of AC and D is the midpoint of EC.

△ACE, B is the midpoint of AC and D is the midpoint of EC.-example-1

1 Answer

9 votes

Answer:

See below

Explanation:


1.\:\:\overline{BD}||\overline{AE}

(By Midsegment theorem)


2.\:\:m\angle 1=48\degree\implies m\angle 4=48\degree

(
\angle 1\: \&\:\angle 4 are alternate angles)


3.\:\:m\angle 3=25\degree\implies m\angle 2=25\degree

(
\angle 2\: \&\:\angle 3 are vertical angles)


4.\:\:\overline {AE}=17\: cm\implies BD = 8.5\: cm

(By midsegment theorem:
BD=(1)/(2)AE


5.\:\: BD=(1)/(2)AE\\\\\implies (3x+10)=(1)/(2)* (12x+2)\\\\\implies 2(3x +10) = 12x+2\\\\\implies 6x +20= 12x+2\\\\\implies 6x - 12x = 2-20\\\\\implies -6x =-18\\\\\implies x =(-18)/(-6)\\\\\implies x = 3\\\\\implies \overline{BD}= (3* 3 + 10)\\\\=(9+10)\\\\\implies \overline{BD}= (9 + 10)\\\\\implies \huge{\purple{\overline{BD}=19}}

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