Answer:
- savings per week
- Alyssa saves more money per week than Sarah does
- Sarah: (0, 8); Alyssa: (0, 0)
Explanation:
A "rate of change" is usually referring to ...
"something" per "something else"
The "per" signifies division, as in a fraction, so this can also be written ...
"something" / "something else"
When the "something else" is one of it (1 week, for example), the rate is called a "unit rate."
When you're dealing with a graph, the "rate of change" usually refers to the slope of the line or curve on the graph. That is why it is computed as ...
rate of change = (vertical change)/(horizontal change)
So, you can find what the "something" is by looking at the chart label and the vertical axis label. You can find what the "something else" is by looking at the horizontal axis label.
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1. The rates of change in this problem represent ...
total savings $ per week
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2. Alyssa's higher rate of change means Alyssa's savings per week are higher than Sarah's.
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3. The "initial value" is the value of the curve or line where the number on the horizontal axis is zero (0). It is usually, but not always, at the left side of the graph. It is also often called the "y-intercept", because it it the value where the curve intercepts the vertical (y) axis. Here, you're asked for an ordered pair, so you want the (x, y) values at that point. We've already said the x-value is zero.
Sarah's initial value: (0, 8)
Alyssa's initial value: (0, 0)