**Donna ,
a 4th grader, makes some great graphs**

**Don
asked Donna
**** to
graph x ^{2} + y^{2} = 25; she found (0,5) and (5,0) that
worked, then found she could use negatives as well.**

**Don asked**
**Donna
****to****
change the equation some way, then graph the
new equation. She chose ****
x ^{2} + y^{3}
= 25, which really didn't surprise Don, and was a great choice. Why? Because Don
wasn't sure what the graph would look like! This took finding the cube root of a
number on the calculator, which **

**They graphed ****D****onna****'s equation ****
x ^{2} + y^{3}
= 25 **

**Don asked**
**Donna
****to****
change the equation again some way, then
graph this new equation. She chose ****
x ^{3}
+ y^{2} = 25 . It got more interesting!**

**The** **
interesting thing ****Donna
****did, without knowing it, was to create the mathematical
inverse of the graph of ****
x ^{2} + y^{3}
= 25, **

**Great job ****D****onna
!!!**

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