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)
Let's see what i can do..
So you need lengths AE and CE
Apparently Angle ADC is not a right angle?
First, we know that DB=DC=√92−32=6√2, which means CB=12√2
Also, note that △CEB∼△ADB 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 912√2=3CE, meaning CE=4√2.
To solve for AE, we use the Pythagorean Theorem on △AEC, and find that AE=√92−4√22=7
Ohhhh so triangle CEB is similar to the congruent right triangles in the middle
That makes sense thanks!
Now that I think of it, here's another way of reaching the same answer.
We already know that CB=12√2 (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=(12√2)2=288.
Subtracting the two equations gives us 18b+81=207, meaning b=7.
Plugging this into the first equation also gives us a=4√2