15x15= 225
15x + 105= 225
15x= 225-105
15x= 120
X=8
X+ (x+1) + (x+2) + (x+3)…etc all the way up too +(x+14)=225
The first five numbers of the set: 8, 9, 10, 11, 12
Answer:
b=12
Step-by-step explanation:
3b +24= b +48
-24 -24
3b = b+ 24
-b -b
2b = 24
÷2 ÷2
b=12
Answer: 
Step-by-step explanation: