in the given figure ABCD is a rhombus and angle ACB is 45 degree find the angle ADC
Answers
Answer:
135°
Step-by-step explanation:
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Step-by-step explanation:
Given:-
in the given figure ABCD is a rhombus and angle ACB is 45 degree
To find:-
find the angle ADC
Solution:-
Given that:
ABCD is a rhombus
AC and BD are the two diagonals
we know that
In a rhombus the diagonals perpendicular bisectors to each other
angle COD = angle BOC = angle AOB =
angle DOA = 90°
Now, In ABCD rhombus ,
AD || BC and AC is a transversal then
angle ACB =angle CAD
(alternative interior angles)
and
angle COD = 90°
Now,
In ∆AOD,
angle ADO + angle CAD + angle AOD = 180°
(The sum of all angles in a triangle is 180°)
=>angle ADO +45°+90°=180°
=>angle ADO+135°=180°
=>angle ADO= 180°-135°
=>angle ADO = 45°
=>angle ADB = 45°
and in ∆ABC ,
AB = BC =>angle BAC = angle BCA
(angles opposite to equal sides are equal)
angle BAC = angle BCA =45°
in ∆ABC
angle BCA+angle BAC+angle ABC = 180°
=>45°+45°+angle ABC = 180°
=>angle ABC +90°= 180°
=>angle ABC = 180°-90°
=>angle ABC = 90°
we know that
Opposite angles are equal in a rhombus
=>angle ABC = angle ADC
angle ADC = 90°
Answer:-
Angle ADC for the given problem is 90°
Used formula:-
- angles opposite to equal sides are equal
- Opposite angles are equal in a rhombus
- Opposite sides are equal in a rhombus