Geometry Question Help (1 Viewer)

sannous1

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Hey can someone help me with these questions, im not sure if my answers are correct.
 

lolokay

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i) by corresponding angles being equal,
ii) ADE is similar to ABC (AAA). AB = AC hence AD = AE. AB = AD + DB = AC = AE + EC; so DB = EC
iii) BC is common, DB = BC, angles DBC and ECB are equal, therefore congruent by SAS
 

sannous1

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hey thanku, see for (ii), do i have to give reasons ? my teacher said yes
 

tommykins

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sannous1 said:
hey thanku, see for (ii), do i have to give reasons ? my teacher said yes
For proof questions, every statement you do MUST have a reason, do NOT assume anything.

If there are two vertically opposite angles, you MUST state that.
 

sannous1

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lolokay said:
i) by corresponding angles being equal,
ii) ADE is similar to ABC (AAA). AB = AC hence AD = AE. AB = AD + DB = AC = AE + EC; so DB = EC
iii) BC is common, DB = BC, angles DBC and ECB are equal, therefore congruent by SAS
so for (ii) i rote
In Triangle DBE and Triangle DEC
AB=AC (given)
AD=AE ( Proved from (i))
AB= AD+DB
AC= AE +EC
Therefore DB= EC

is this correct?,

or do i say in triangle ADE and triangle ABC in the beginning ?

PLEASE its a mini assignment thanks u guys
 

tommykins

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sannous1 said:
so for (ii) i rote
In Triangle DBE and Triangle DEC
AB=AC (given)
AD=AE (sides of isos triangle equal proven in i))
AB= AD+DB
AC= AE +EC
Therefore DB= EC

is this correct?,

or do i say in triangle ADE and triangle ABC in the beginning ?

PLEASE its a mini assignment thanks u guys
Only fixed one small bit, but it all seems good.
 

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