Answer:
$1.12
Step-by-step explanation:
One way to solve this problem is through an algebraic equation. Set up the equation like this, 
. This equation works because 3.28 is subtracted from 10, which represents how much was spent in total. Then, this is equal to 6x, which represents the total cost of six keys.
So, to solve first subtract 3.28 from 10, this gives you 6.72. Then, divide both sides by 6. This equals 1.12, which is the cost of each key.
The answer is y=-2/3x+3 :)
Answer:
Slope is .18
Step-by-step explanation
Find two points along the line.
Calculate slope using 
.
I used the points (1985, .21) and (1990, .30).
- 3 and 2 are the answers because at each of those points the graph line is rising.
There's no way to tell if we can't see the inequality.
