MathRevolution wrote:
If (r+t)/(r-t)>0, is r>t?
1) t>0
2) r>0
*An answer will be posted in 2 days.
The question can be rewritten as:
\(\frac{(r+t)}{(r-t)}\)>0
Now this is possible when either both numerator and denominator are positive.
or both numerator and denominator are negative
Case 1:
r+t > 0
r-t > 0
Add these two: 2r> 0;
r > 0 --> This is my new question. Show that r> 0
Case 1:
r+t < 0
r-t < 0
Add these two: 2r < 0;
r < 0 --> This is my new question. Show that r < 0
So if there is any option that shows that r > 0 or less than 0 --> I can get answer.
Statement 1Gives no idea about r. Not sufficient.
Statement 2We got our answer.
r > 0
This means I can say that
r+t > 0 (r > -t)
r-t > 0
(r > t) --> This is what we wanted to show. Unique answer obtained.
B is the answer.