Quickkk please help and how all work

2x+4y=-6
3x-y=5

Henry is an avid reader, he devours 90 pages in half an hour how many pages has henry read per minute?

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

Ade and abc are similar. which best explains why the slope of the line between points a and d is the same as the slope between points a and b?