Answer: 
a=-3
b=-9
Step-by-step explanation:

Correct Question:
At a bake sale, plates of cookies, p, are sold for $5 each. The amount of money from the sale of cookies is expressed as dollars, d. Which equation represents the earnings of the bake sale?
1. p = 5d
2. d = p + 5
3. d = 5p
Answer:
3. d = 5p
Step-by-step explanation:
As one plate of cookies price is 5 $
The d is expressed as numbers of dollars which are earned.
Earnings = d = 5 x number of plates sold (p)
therefore
d = 5p
Answer:
To find the average rate of change, we divide the change in the output value by the change in the input value.
Step-by-step explanation:
Answer:
30 minutes
Step-by-step explanation:
First you can break down the percent and the time into a fraction
You can divide it by 2
so 2%/1 (2% in 1 minute)
Then you find the amount of time it would take to paint the whole bookcase
2 * 100 = 50
So time to paint the whole bookcase would be 50
50 - 20 = 30
1% sales tax.
900 x 0.01 = 909
I Hope this helps