Answer: 7, 21, and 23
Step-by-step explanation:
Let the 3 numbers be x (1st number), y (2nd number), and z (3rd number).
The 2nd number is 3 times the first:
y=3x (Eq. 1)
The 3rd number is 2 more than the 2nd:
z= y+2 (Eq. 2)
7 less than twice the 2nd is equal to 12 more than the 3rd:
2y-7=z+12 (Eq. 3)
Rewrite the Eq. 3 by substituting z=y+2 and solve for y:
2y-7=y+2+12
y=21
Input y=21 into Eq. 1 and Eq. 2 to get x and z:
In Eq. 1:
21= 3x
x= 7
In Eq. 2:
z= 21+2
z= 23
