Answer: 13
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Step-by-step explanation:
We have the two points
and
Apply the distance formula to them.
The distance from Sara's house to the school is exactly 13 km.
An alternative is to use the pythagorean theorem. The distance formula is effectively based on this theorem.
To check the answer, you can use a tool like GeoGebra to plot the two points given. Then draw a segment between them. It should show "13" as the segment length. That app also has a "distance" tool as an alternative. So there are a few ways to get the answer, and to check it as well.