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so I'm looking for lengths AE and CE

so I'm trying to figure out angle CAE and I determined that 180-DAB+CAD=CAE (DAB = CAD)

I also tried proving that angle CAE was 2*angle B by flipping and rotating the triangle to make a rectangle and then adding angles  ACD and B,

 then I assumed because  CAe was on the same line and ACD + B made a 90 degree angle that CAE = ACD + B

The sidelengths of EA and CE are not equal

How should I continue

(if you have trouble deciphering my jumbled brain let me know, I'm not sure how to make a diagram for what I'm saying)

 Feb 2, 2023
edited by YourAverageDummy  Feb 2, 2023
 #1
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Let's see what i can do..

So you need lengths AE and CE

Apparently Angle ADC is not a right angle?

 Feb 2, 2023
 #2
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First, we know that DB=DC=9232=62, which means CB=122

 

Also, note that CEBADB by AAA. This is because both triangles have a right angle and share B, which means that all 3 traingles have the same angles, and thus, are similar. 

 

Now, by similiar triangles, we have ABCB=ADCE. Substituting what we know, we have 9122=3CE, meaning CE=42.

 

To solve for AE, we use the Pythagorean Theorem on AEC, and find that AE=92422=7

 Feb 2, 2023
 #4
avatar+163 
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Ohhhh so triangle  CEB is similar to the congruent right triangles in the middle

That makes sense thanks!

YourAverageDummy  Feb 2, 2023
 #3
avatar+2668 
+3

Now that I think of it, here's another way of reaching the same answer. 

We already know that CB=122 (look at the other solution to see how)

 

Now, let CE=a and AE=b. We have a2+b2=81, and a2+(b+9)2=(122)2=288

 

Subtracting the two equations gives us 18b+81=207, meaning b=7

 

Plugging this into the first equation also gives us a=42

 Feb 2, 2023

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