扫描二维码，直接登录
题库 / Prep2007E1-DS-62
In isosceles ~$\Delta $~RST what is the measure of ~$\angle $~R ?
(1) The measure of ~$\angle $~T is 100°.
(2) The measure of ~$\angle $~S is 40°.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
还没有题目讲解（毕出老师会陆续发布对官方考题的解读，请保持关注）。
只要一个条件就够的时候就暂时不考虑两个情况加一起合适的情况
其实一个①就够了 因为100度不可能是等腰三角形的腰
isosceles triangle 等腰三角形
脑子瓦特了。
1）就知道剩下那两个角肯定是相等的两个，因为合为180. 做的时候还在想我怎么知道这哪个角是相等的两个？三角形命名规则？
卧槽，真是瓦特了。