+0  
 
+1
44
5
avatar

I have found two answers but they are incorecct for my two questions

1. Let G be the center of equilateral triangle XYZ. A dilation centered at G with scale factor \(-\frac{2}{3} \)is applied to triangle XYZ, to obtain triangle X'Y'Z'. Let A be the area of the region that is contained in both triangles XYZ and X'Y'Z'. Find \(\frac{A}{[XYZ]}\).

I found the answer 4/9 but the website i use said its not correct... 

 

2. A square ABCD has an area of 4. The square is then dilated with a scale factor of x, producing a square A'B'C'D' of area 9. Find the sum of all possible values of x.

i found two answers 1.5 or -1.5 because the hint i was given was can scale factors be negative. I thought that there was only 1 answer 1.5 should i just add the two to get 0? 

EDIT: The correct answer was 0! I wasnt thinking about the part where it said sum. It clicked once I wrote it out here. 

 

Please help with number 1!

Thank you so much!

 Jul 22, 2020
edited by Guest  Jul 22, 2020
 #1
avatar
0

1. The answer is 2/5.

 Jul 22, 2020
 #2
avatar
0

I am sorry but how did you get that? That is also incorrect

Guest Jul 22, 2020
 #3
avatar+1046 
+1

Important:::  If the value of scale factor k is negative, the dilation takes place in the opposite direction from the center of dilation on the same straight line containing the center and the pre-image point.

 

A / [xyz] = 0.407407407 = 11/27  laugh

 

 Jul 23, 2020
edited by Dragan  Jul 23, 2020
edited by Dragan  Jul 23, 2020
 #4
avatar
+1

OH wow thank you!! I understand now becuase of your note at the top so I can rember to use that in similar problems. Thank you so much!

Guest Jul 23, 2020
 #5
avatar+1046 
0

You're very welcome!smiley

Dragan  Jul 23, 2020

14 Online Users

avatar
avatar
avatar
avatar