The number of tulips that Marko has in his yard can be represented by the following formula:
x = 20 + 5(y)
where "x" is the number of tulips Marko has,
and "y" is the number of years that have passed.
If 7 years have passed, we substitute this number for "y"
so,
x = 20 + 5(7)
= 20 + 35
= 55
Therefore, Marko will have 55 tulips in 7 years.
