Answer:
Nikki is 16, Travis is 8
Step-by-step explanation:
We need to set up an equation
If x is Nikki's age, then Travis' would x-8 since Nikki is 8 years older.
x+(x-8)=24
2x-8=24
2x=32
x=16
the oldest is 16 and the other sibling Travis =8
x+y=24
x-y=8 ⇒ x=8+y
solve by substitute
8+y+y=24
2y=24-8
2y=16
y=16/2=8
x=8+y
x=8+8=16
y=8
