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ABCD is a rectangle. Find angles a and b to the nearest degree

User Sijia Din
by
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1 Answer

3 votes

Solution

Given, ABCD is a rectangle AC is diagonal

Then AD=BC and AB=CD

And ∠ABC=∠BCA=∠CDA=∠DAB=90

0

In ΔABC and ΔADC

∠ABC=∠ADC (Angle of rectangle)

AB=DC (Opposite side of rectangle )

AC=AC (Common side)

∴ΔABC≅ΔADC

∴∠ACD=∠ACB

∵∠ACD+∠ACB=90

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..........[Angle ACB is the angle of rectangle]

∴2∠ACD=90

0

⇒∠ACD=45

0

User Manish Karena
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4.7k points