Circle Geometry Question (1 Viewer)

lychnobity

Active Member
Joined
Mar 9, 2008
Messages
1,292
Gender
Undisclosed
HSC
2009
In the diagram, AE is a diameter. Prove that angle ABC + angle CDE = 270.
 

The Nomad

Member
Joined
Oct 11, 2009
Messages
123
Gender
Male
HSC
2010
Angle EBC + Angle CDE = 180 (opposite angles are supplementary in a cyclic quadrilateral)
Angle ABE = 90 (subtended by diameter AE)

ABE + EBC + CDE = 180 + 90 = 270.

But ABE + EBC = ABC.

So ABC + CDE = 270.
 

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
lol, why are you asking this. Ext 1 HSC is over lol.
 

lychnobity

Active Member
Joined
Mar 9, 2008
Messages
1,292
Gender
Undisclosed
HSC
2009
Not my fault! I have to look smart in front of the year 11 kid asking me.
 

The Nomad

Member
Joined
Oct 11, 2009
Messages
123
Gender
Male
HSC
2010
I'd swap 10 units of maths for my HSC subjects anyway, so I sure don't blame you for asking even though the exam is over :p
 

The Nomad

Member
Joined
Oct 11, 2009
Messages
123
Gender
Male
HSC
2010
There's always university maths.

Though I wonder how boring life gets once you finish your PhD.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top