In 45 years, Gabriela will be 4 times as old as she is right now.
Let a be Gabriela's age. we have:
a + 45 = 4a
Subtract a from each side:
3a = 45
Divide each side by a
a = 15
Let a be Gabriela's age. we have:
a + 45 = 4a
Subtract a from each side:
3a = 45
Divide each side by a
a = 15