Jill is swimming laps in a pool. The table shows how the total distance she swims depends on the number of laps she does. Number of Laps - Total Distance (Meters)
5 250
10 500
15 ?
20 1,000
25 1,250
A. 50
B. 75
C. 550
D. 750

the entire expression should be subtracted from 30. to subtract the quantity, distribute the negative sign, which changes the signs on the terms. so, the –2 changes to positive and gets added to 30 instead of subtracted from it.

hope this ! ^w^