Question

Jackson wants to purchase flowers to plant on Mother's day for his mom. If each plant costs $1.25 and he has $10 to spend, write an equation for the amount of money, y, Jackson will have left over after purchasing x amount of plants

Answer 1

Maybe this would be easier to see if you had easier numbers. If you had $5, and each plant costs $2, how would you find out how much money, y, you would have left over after buying x = 2 plants?

Answer 2

Actually, for you particular problem, it's even easier...

If each plant costs $1.25, then
# plants cost per plant total cost left over from $10
1 $1.25 1.25 10 - 1.25 = 8.75
2 $1.25 2.50 10 - 2.50 = 7.50
3 $1.25 3.75 10 - 3.75 = 6.25
etc...

So the amount left over from $10 is ten dollars minus (1.25 times the number of plants)

Answer 3

since the amount left over is called "y"
and the number of plants purchased is called "x"

Another way to write the sentence I wrote above... "the amount left over from $10 is ten dollars minus (1.25 times the number of plants)"

is like this:
y = 10 - 1.25x

amount
left = 10 minus (1.25 times # of plants)
over