Question

Triangle ABC is isosceles, with AB = AC.
Angle ACD = 113°

Work out the size of angle BAC.

Answer 1

Step-by-step explanation:

Triangle ABC is isosceles, with AB = AC.

Angle ACD = 113°

anglel ACB = 180 - 113

angle ACB = 67

angle ACB = angle ABC = 67

( as ∆ ABC is isosceles ∆ )

angle x = 180 - 2 ( 67 )

x = 180 - 2 ( 67 )

angle sum property of a ∆

x = 180 - 134

x = 46

so x is 46 °

Answer 2

Answer:

☆BAC=46°

Step-by-step explanation:

◇To find:

☆Value of angle BAC

◇Given:

☆Angle ACD=113°

◇Note:

○In iscoleses triangle two angles in the base are equal to each other

○A straight line =180°

○Sum of all Interior angles of triangle =180°

◇Solution:

☆ACD+ACB=180 (linear pair)

=>113+ACB=180

=>ACB=180-113

=>ACB=67

☆Therefore,

○ACB=67°

☆Now ,

ACB+ABC+BAC=180

=>67+67+x=180 (ACB=ABC=67)

=>134+x=180

=>x=180-134

=>x=46

◇Hence:

☆BAC=x=46°

hope it helps....