Answer:
Savannah's age = 6 years
Step-by-step explanation:
Let
Savannah's age = x
Dylan's age = 15
Dylan is 15, which is 3 years older than twice his sister Savannah’s age
Dylan = 2x + 3
Find Savannah's age
2x + 3 = 15
Subtract 3 from both sides
2x + 3 - 3 = 15 - 3
2x = 12
Divide both sides by 2
2x / 2 = 12 / 2
x = 6
Therefore,
Savannah's age = x
= 6 years
Dylan's age = 2x +3
= 2*6 + 3
= 12 + 3
= 15 years