(Score for Question 5:
of 5 points)
5. The coordinates of the vertices of AABC are A(-5,2), B(-1,-1), and C(5,7). Angela is trying to determine
whether this shape is a right triangle or not. She has made a mistake in the work below the graph. Explain the
mistake and show the correct solution.
Hint: When explaining the mistake, make sure you identify how it is wrong AND how it needs to be corrected.
Angela's solution:
slope of AB =
slope of BC =
Answer:
-1-2
-1-(-5)
5-(-1)
7-(-1)
-
7-2
5-(-5)
== ²/20
slope of AC =-
Since none of the slopes are opposite, reciprocals, there are no right angles. Therefore, this cannot be a right
triangle.
5
10
=
1/2