Answer:
12
Step-by-step explanation:
1
2
3
4
5
6
7
8
9
10
11
1+2+3+4+5+6+7+8+9+10+11+12=78
c = 24
8*3=c
-390 PLEASE GIVE BRAINLIEST
y = 310 - 25(28)
y = 310 - 700
y = -390