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the graph shows triangles abc and stu. is abc similar to stu? justify y…

Question

the graph shows triangles abc and stu.
is abc similar to stu? justify your answer.
yes, because a dilation by a scale factor of \\( \frac { 1 } { 2 } \\) centered at point b followed by a rotation \\( 180 ^ { \circ } \\) around the origin maps abc onto stu.
yes, because a dilation by a scale factor of \\( \frac { 1 } { 2 } \\) centered at point a followed by a rotation \\( 180 ^ { \circ } \\) around the origin maps abc onto stu.
no, because \\( \angle b \\) and \\( \angle t \\) do not have the same measure.

Explanation:

Step1: Calculate the side lengths

Use the distance formula \(d=\sqrt{(x_2 - x_1)^2+(y_2 - y_1)^2}\).
For \(\triangle ABC\):

  • \(AB=\sqrt{(-3+8)^2+(10 - 6)^2}=\sqrt{25 + 16}=\sqrt{41}\)
  • \(BC=\sqrt{(2+3)^2+(-2 - 10)^2}=\sqrt{25+144}=\sqrt{169} = 13\)
  • \(AC=\sqrt{(2+8)^2+(-2 - 6)^2}=\sqrt{100 + 64}=\sqrt{164}\)

For \(\triangle STU\):

  • \(ST=\sqrt{(5 - 2)^2+(-9+10)^2}=\sqrt{9 + 1}=\sqrt{10}\) (This is wrong approach, we can also use the property of dilation. If we assume a dilation centered at a wrong point, the side - length ratio won't match. But if we check the angles.

Another way: We know that if two triangles are similar, their corresponding angles are equal.
If we consider the transformation. A dilation centered at \(A\) with scale factor \(\frac{1}{2}\) will not map \(ABC\) to \(STU\) correctly.
If we consider the rotation and dilation.
Let's check the angle - angle similarity.
We can also use the fact that if a dilation is centered at \(B\) with scale factor \(\frac{1}{2}\), the position won't be correct.
But if we check the slope of the sides to find angles.
The slope of \(AB\) in \(\triangle ABC\): \(m_{AB}=\frac{10 - 6}{-3+8}=\frac{4}{5}\)
The slope of \(ST\) in \(\triangle STU\): \(m_{ST}=\frac{-9 + 10}{5 - 2}=\frac{1}{3}\) (This is also a wrong way. The correct way is to use the property of similarity transformation.
Since there is no dilation - rotation combination (centered at \(A\) or \(B\)) that can map \(ABC\) to \(STU\) such that the side - length ratios are equal and angles are equal. And we can observe from the graph (by counting the grid units for side - lengths in a non - formal way, assume \(AB\) spans \(5\) units in \(x\) - direction and \(4\) units in \(y\) - direction (approximate from grid), \(ST\) spans \(3\) units in \(x\) - direction and \(1\) unit in \(y\) - direction. The ratios are not equal. Also, if we check the angle \(\angle B\) and \(\angle T\) (by the direction of the sides forming the angles), they are not equal.

Answer:

No, because \(\angle B\) and \(\angle T\) do not have the same measure.