Answer:
Lisa must get an 88.75 or higher to stay in between 80 and 90.
Step-by-step explanation:
In mathematics, mean average means to take the sum of all the numbers and divide the sum by the number of elements in the set.
Add up the numbers.
<span>21 + 23 + 25 + 25 + 26 + 28 + 28 + 28 + 31 + 33 = 268
Divide by the number of elements in the set. Which is 10.
268 / 10 = 26.8
So, the answer to this question is 26.8</span>
Is this a multiple choice or no
Same I hate tiktoc for showing me happy couples
See the attached graph
<h2>
Explanation:</h2>
Hello! Remember to write complete questions in order to get good and exact answers. Here you don't provide any system so I couldn't help you in an exact way, but in a general manner. When solving systems by graphing we just need to find the points of intersection of the graphs of the functions that built up the system.
Suppose you have the following system of linear equation:

yBy using graphing tools, we get the graph shown below. As you can see, the point of intersection of both lines is 
<h2>Learn more:</h2>
Solving systems by graphing: brainly.com/question/13799715
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