Sat math question

<p>ok. so here's the question - </p>

<p>points P,Q,R,S,T and U are all different points lying in the same plane. Points P,Q and U lie on the same line. The line through points P and Q is perpendicular to the line through R and S. The line through R and S is perpendicular to the line through points T and U. Which of the following sets contains points that must lie on the same line?</p>

<p>A. {P, Q, R}</p>

<p>B. {Q, R, S}</p>

<p>C. {Q, R, T)</p>

<p>D. {Q, T, U}</p>

<p>E. {R, T, U)</p>

<p>Please give the explanation along with the answer...thanks! :)</p>

<p>If you draw a picture, the answer becomes clear. Draw two perpendicular lines, one horizontal and one vertical. On the horizontal line put points P, Q. and U (doesn't matter where). On the vertical line put points R and S (again, it doesn't matter where). You should now see that point T must be on the horizontal line. So P, Q, U and T are all on the same line. Thus, the answer is choice (D).</p>