Hello there!
Your question asks to make an equation with the information that was given.
Answer: y = -5x + 30
In order to make an equation for your question. We would be making an equation with the formula: y = mx + b.
Formula: y = mx + b
m = change
x = amount of ice cream
b = starting value
We would need to gather the key information from the question.
Key information:
You have $30
Each ice cream cost $5
With the information above, we can make an equation for the question.
What we know is that you started with $30, so that means that 30 would be your b value (starting value).
Your equation should look like this:
y = mx + 30
Now, we know that each ice cream cost $5, but since we're paying for the ice cream, we would subtract that from our starting value. This means that our change would be -5, since we are taking away $5 each time we buy ice cream.
Your equation should look like this:
y = -5x + 30
The equation above would be the equation for your question.
We would do nothing to x but just leave it as is, since we don't know how many ice creams you're going to buy.
y = -5x + 30 should be your FINAL answer.
I hope this helps!
Best regards, MasterInvestor