The ratio of money in Brian’s wallet to Collins wallet one day was 7:2. Brian spent £39 that day. Brian now had £4 less than colin. How much did Colin initially have?

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

Which of the following is the true for f(x) = 5cos

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