46.6k views
2 votes
∆ABC and ∆PQR are similar. ∆ABC is dilated by a scale factor of 1.25 and rotated 45° counterclockwise about point B to form ∆PQR. The side lengths of ∆ABC are , 5 units; , 4.2 units; and , 4 units. Match each side of ∆PQR to its length.

User Eleno
by
6.2k points

2 Answers

1 vote

After dilating
\( \Delta ABC \) by a scale factor of 1.25 and rotating it 45° counterclockwise about point B, the side lengths of
\( \Delta PQR \) are PQ = 6.25 units, QR = 5.25 units, and PR = 5 units.

Let's denote the side lengths of
\( \Delta ABC \) as
\( AB, BC, \) and
\( AC \), and the corresponding side lengths of
\( \Delta PQR \) as PQ, QR and PR.

Given that
\( \Delta ABC \) is dilated by a scale factor of 1.25 and rotated 45° counterclockwise about point B, we can determine the side lengths of
\( \Delta PQR \) as follows:

1. Dilating by a scale factor of 1.25:

-
\( PQ = 1.25 * AB \)

-
\( QR = 1.25 * BC \)

-
\( PR = 1.25 * AC \)

2. Rotating 45° counterclockwise about point B:

- PQ, QR, and PR are now the rotated side lengths.

Now, let's substitute the given side lengths of
\( \Delta ABC \) to find the corresponding side lengths of
\( \Delta PQR \):

Given:

- AB = 5 units

- BC = 4.2 units

- AC = 4 units

Substitute these values:

1. Dilating by a scale factor of 1.25:

-
\( PQ = 1.25 * 5 = 6.25 \) units

-
\( QR = 1.25 * 4.2 = 5.25 \) units

-
\( PR = 1.25 * 4 = 5 \) units

2. Rotating 45° counterclockwise about point B:

- The side lengths PQ, QR, and PR after rotation are the final side lengths.

So, the matched side lengths of
\( \Delta PQR \) are:

- PQ = 6.25 units

- QR = 5.25 units

- PR = 5 units

User ChyBy
by
5.8k points
6 votes
This is the concept of transformation of figures, given that ΔABC is similar to ΔPQR, the sides of ABC are 5 units, 4.2 units and 4 units. Since the two triangles are similar and PQR is the image of ABC under the dilation 1.25, the sides of PQR will be:
(5*1.25),(4.2*1.25),(4*1.25)
this will give us:
6.25, 5.25, 5
The length of the sides of PQR are 6.25 units, 5.25 units and 5 units
User Robbie Wareham
by
6.3k points