Why is the answer in this problem
-13 + 9 = -4 a negative but not in this problem -5 + 6 = 1

If an athlete can bike 6 miles in 25 minutes, how many miles will he bike in an hour and half if he continues to bike at the same rate?

Find the equation using the point (4,8)

Type the correct answer in each box, round your answers to the nearest integer 20 25 30 in the figure, the perimeter of hexagon abcdef is approximately w units, and its area is square units