[問題]OG(11th)DS-Q27

[neverinmind]

(Chart: A triangle with its three angles, x, y, and z)
(x, y, and z unit: degrees)

Is the triangle above equilateral?
(1) x=y
(2) z=60

Answer: C

I suppose that the answer B only should be sufficient. Do you have any comments?

Really appreciate!



By the way, is there anyone who knows where I can find detailed description of OG11th Math? Just can't find it no matter in here or in CD.

Thank you all, guys! Hope you all can get achieve ur goals!

[FrankChang]

(2)Z=60, what if A=90 and B=30!?
Insufficient.