Can someone explain this to me?
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Sure thing.
To find the distance, you will need to use the distance formula:
[tex]\sqrt{(x_{2}-x_{1})^2+(y_{2}-y_{1)^2}[/tex]
So, you already are given the points, let's plug them in.
(3,-5) and (-3,9)
3: [tex] x_{1}[/tex]
-5: [tex] y_{1}[/tex]
-3: [tex] x_{2}[/tex]
9: [tex] y_{2}[/tex]
Let's plug in these values into the equation.
[tex]\sqrt{(-3-3)^2+(9+5)^2}[/tex]
Simplify.
[tex]\sqrt{36+196}[/tex]
[tex]\sqrt{232}[/tex]
Final Answer:
[tex]\sqrt{232}[/tex]
You should leave your answer in radical form because it gives you the exact distance between the points instead of rounding.