If t100=1400  and  t400=1100  of an A. P, and kth  term is 1, then k50=  ___

How do the graphs of y = 1/x and y=5/x+6 compare?

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1