Answer:
Lisa is 5 years old
Step-by-step explanation:
we can make an equation like
4x=15+x
X can represent Lisa’s current age
Now just solve for X
3x=15
x=5
And we can check
If Lisa is 5 years old now
In 15 years she would be 20
And 20 is 4 times as 5 which Is her current age
So Lisa is 5 years old now.