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Help with this GCSE Maths question please?

I've added a picture of the question-IMG_8517.jpg
image.jpg Hope this helps - if it doesnt make sense i can type it out for you? :smile:
Original post by epoddoulc
I've added a picture of the question-IMG_8517.jpg


^^ i replied but forgot to tag you in it
Reply 3
Original post by Scarlett4
^^ i replied but forgot to tag you in it


Can you explain it to me please I'm a noob
48
Original post by epoddoulc
Can you explain it to me please I'm a noob


Its just a process of seeing the isosceles triangles and alternate angles.
Reply 6
Original post by roryburke901
Its just a process of seeing the isosceles triangles and alternate angles.


Is there a video or website which you'd advise me to look at?
Original post by epoddoulc
I've added a picture of the question-IMG_8517.jpg


So, as triangle CBE is isoceles (sides CB and BE are equal in length), angle BCE is therefore 48 degrees. Angles in a triangle add to 180 degrees so angle EBC is 180 - 48x2 which is 84 degrees. Next, angles on a straight line add to 180 degrees so 84 degrees and angle ABC must equal 180 degrees. Therefore (by taking 180 degrees away from 84 degrees) leaves you with 96 degrees as angle ABC. As triangles ABC and ADC are the same, angle ADC equals 96 degrees. Finally, the isoceles triangle means that angle CAD and angle DCA are equal, therefore angle DCA is 180 - 96 = 84 degrees. Therefore dividing that by 2 (as this has got to split down into both angle CAD and DCA , angle DCA is 42 degrees.

Sorry if this was a long explanation, but I hope you understand now how to do it. Good luck for your exam tomorrow.
Original post by epoddoulc
Is there a video or website which you'd advise me to look at?


I'm not really sure to be honest.
Reply 9
Original post by Speedbird129
So, as triangle CBE is isoceles (sides CB and BE are equal in length), angle BCE is therefore 48 degrees. Angles in a triangle add to 180 degrees so angle EBC is 180 - 48x2 which is 84 degrees. Next, angles on a straight line add to 180 degrees so 84 degrees and angle ABC must equal 180 degrees. Therefore (by taking 180 degrees away from 84 degrees) leaves you with 96 degrees as angle ABC. As triangles ABC and ADC are the same, angle ADC equals 96 degrees. Finally, the isoceles triangle means that angle CAD and angle DCA are equal, therefore angle DCA is 180 - 96 = 84 degrees. Therefore dividing that by 2 (as this has got to split down into both angle CAD and DCA , angle DCA is 42 degrees.

Sorry if this was a long explanation, but I hope you understand now how to do it. Good luck for your exam tomorrow.


Thanks, this really helped and refreshed my memory.
Original post by epoddoulc
Thanks, this really helped and refreshed my memory.


Your very welcome :smile:. Good luck in your exam!
Reply 11
Original post by Speedbird129
Your very welcome :smile:. Good luck in your exam!

Thanks, means a lot:smile:

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