Question

Derek determines that triangle CGD is an isosceles triangle.

Which statement best describes Derek’s conclusion?

It is correct because angle CGD = 108°, angle GCD = 36°, and angle GDC = 36°.

It is correct because angle CGD = 72°, angle GCD = 72°, and angle GDC = 36°.

It is incorrect because angle CGD = 72°, angle GCD = 74°, and angle GDC = 34°.

It is incorrect because angle CGD = 108°, angle GCD = 54°, and angle GDC = 18°

Answer 1

@ganeshie8

Answer 2

start wid finding all angles in the triangle CGD

Answer 3

@ganeshie8

Answer 4

find the angles

Answer 5

Erm, how exactly do I do that?

Answer 6

G = 108, cuz vertical angles are equal

Answer 7

C = 90-36 = 54

Answer 8

Find D using triangle sum property

Answer 9

is it 18 ?

Answer 10

yes ! so all different angles we got eh ?

Answer 11

108
54
18

Answer 12

So the last choice?

Answer 13

Yes ! its not an isosceles triangle at all

Answer 14

Thank you!

Answer 15

np :)