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Both triangles seem to be a reflection of each other.
Use the Distance Formula to find the measures of the sides.
Graph:
Conjecture: △ ABC ≅ △ XYZ
See solution.
We are asked to graph triangles ABC and XYZ on the same coordinate plane. To do so, we are going to plot all the given vertices, and then draw the corresponding triangles. Let's start with the points.
We can now connect them.
Let's take a look at the graph we created in Part A. We can see that â–³ XYZ is a reflection of â–³ ABC across the vertical line x=1.
If two figures are a reflection of one another, then their corresponding sides are the same length. This suggests that the triangles are congruent. We can set the following conjecture. Conjecture: △ ABC ≅ △ XYZ
To prove our conjecture, it is enough to show that the corresponding sides in the triangles are congruent. We can do that using the Distance Formula.
d = sqrt((x_2-x_1)^2 + (y_2-y_1)^2)
Let's find the measure of AB by substituting the coordinates of points A and B in the formula.
Substitute ( -3,-5) & ( -1,-1)
Similarly, let's find the measure of XY.
Substitute ( 5,-5) & ( 3,-1)
Consequently, we have AB ≅ XY. The lengths of the remaining sides are summarized in the table below.
| Side | Distance | Measure |
|---|---|---|
| AC | AC = sqrt((-1-(-3))^2 + (-5-(-5))^2) | 2 |
| XZ | XZ = sqrt((3-5)^2 + (-5-(-5))^2) | 2 |
| BC | BC = sqrt((-1-(-1))^2 + (-5-(-1))^2) | 4 |
| YZ | YZ = sqrt((3-3)^2 + (-5-(-1))^2) | 4 |
We got AC≅XZ and BC≅YZ. Therefore, by the Side-Side-Side (SSS) Congruence Postulate we get △ ABC ≅ △ XYZ.