Ok so 5x20 is 100 and 3x20 is 60 then add 3 is 63 apps that she downloaded then 100-63 is 37 apps that she still has space for.
Answer:

Step-by-step explanation:
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The distance between the two points is 13.
Answer:
(-1,4) This is the solution for the given system
Step-by-step explanation:
The first graph is shown in the first picture attached, it has the points (3,0) and (0,3)
The other graph is attached as well
The solution for this system is the interception between the graph