Answer:
The measure of ∠A = 107.5°
Step-by-step explanation:
Given that
ABCD is a kite such that
AB = BC and AD = DC
Join A and C
Since AB = BC
→ ∠BAC = ∠BCA
Since , the angles opposite to equal sides are equal.
Let ∠BAC = ∠BCA = x°
and
Since AD = DC
→ ∠CAD = ∠ACD
Since , the angles opposite to equal sides are equal.
Let ∠CAD = ∠ACD = y°
Now
In ∆ ADC ,
∠ADC + ∠CAD + ∠ACD = 180°
Since , the sum of the all angles in a triangle is 180°
⇛ 30° + y°+ y° = 180°
⇛ 30°+2y° = 180°
⇛ 2y° = 180°-30°
⇛ 2y° = 150°
⇛ y° = 150°/2
⇛ y° = 75°
Therefore, ∠CAD = ∠ACD = 75°
and
In ∆ ABC,
∠ ABC + ∠BAC + ∠BCA = 180°
Since , the sum of the all angles in a triangle is 180°
⇛ 115° + x° + x° = 180°
⇛ 115°+2x° = 180°
⇛ 2x° = 180°-115°
⇛ 2x° = 65°
⇛ x° = 65°/2
⇛ x° = 32.5°
Therefore, ∠BAC = ∠BCA = 32.5°
Now, ∠ A = ∠BAC + ∠CAD
⇛ ∠A = 32.5° + 75°
⇛ ∠A = 107.5°
Therefore, ∠A = 107.5°
Answer:-
- ) The measure of ∠ADC = 145°
- ) The measure of ∠A = 107.5°
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ABCD is a kite with AD=AB A= 116° B=2x° D=(5x-147)° Find the size of the smallest angle of the kite.
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