Q5 of 23 Page 178

ABCD is a rectangle AC is diagonal. Find the angles of ∆ACD. Give reasons.


Given:- ABCD is a rectangle


Formula used:- All angles of rectangle are 90°


In right angle triangle


Pythagoras theorem a2+b2=c2


Sin(θ)=


Solution:-


In ΔACD


∠ D=90° [All angles of rectangle are 90° ]


∠ ACD=θ1


And; Sin(θ1) = =


θ1=arc sin()


∠ DAC=θ2


And; Sin(θ2) = =


θ1=arc sin()


Conclusion:-


The angles of Δ ACD are :-


∠ D=90°


∠ DAC=arc sin()


∠ ACD=arc sin()


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