find the distance from the point C to the diagonal

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marinaa11

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Hello, could you, please, help me with the third part of this problem? :) thank you.


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with points B and D you can formulate the equation of the line BD

Then you can use this to find the distance from that line to point C.
 
Consider triangle B1CD. CK is height. There are several ways to express the area of B1CD through a height and a base. This gives you an equation with CD length as the unknown.
 
You could also use the fact that triangle B1CD is similar to triangle CKD. You know all the sides of the former, and one side of the latter.
 
marinaa11 said:
Thank you for your advice. Do you approve?

View attachment 24730
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Yes.

You could instead have found the area as bh/2 = (15)(20)/2 = 150. And if you'd used my similar triangle approach, you'd have k/15 = 20/25, so k = 12.

Doing it two ways and getting the same answers suggests not only is your work appropriate, but it's also correct.
 
Yes, that would be a much easier way. Anyway, I wrote these two options and thereby revised about similar triangle approach. Thanks!!
 
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