Data Sufficiency (Triangles)
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
It's intuitive that either alone is not sufficient, so lets think about both statements together. Lets label some angles here: Let angles QRS=y, RQS=QSR=a, STU=z, UST=TUS=b. Now, y+z=90 because triangle RPT is a right triangle. We observe that y=180-2a and z=180-2b. So 180-2a+180-2b=90, which simplifies to 270-2(a+b)=0. We also observe that a+b+x=180, so a+b=180-x. Then 270-2(180-x)=0, and x=45. So the answer is C.
