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IN Triangle ABC, angle ACB=90 degrees. D and E lie on line AB such that line CD is perpendicular to line AB and line AE=line EB. F lies on line CB such that line EF is perpendicular to line CB. CE=8 and EF=10. In simplest radical form, CD=k times the Sq. root of w all over 9.

2007-01-25 14:22:36 · 2 answers · asked by Quagmire77 1 in Science & Mathematics Mathematics

sorry CE=18

2007-01-26 00:42:23 · update #1

2 answers

By similar triangles, AC = 20.

By Pythagoras on triangle CEF, CF = sqr(18^2 - 10^2) = 4sqr(14).

This makes the coordinate of AE = 20-4sqr(14),10) if the origin were point A. So AE^2 = (20 - 4sqr(14))^2 + 10^2 = 724 - 160sqr(14).

So AB = 2*AE.

So CB^2 = AB^2 - 20^2 = 4( 724 - 160sqr(14)) - 400 = 2496 - 640sqr(14).

By similar triangles, CB/CD = AB/20 = 2*AE/20 = AE/10. So CD = 10*CB/AE

This is 10*sqr[ (2496 - 160sqr(14)]/(724 - 160sqr(14))], which simplifies to

20*sqr[ (156 - 40sqr(14)]/(181 - 40sqr(14))]. Now multiply by the conjugate of the denominator to simplify more. Etc.

2007-01-27 09:31:49 · answer #1 · answered by berkeleychocolate 5 · 0 0

Are you sure the question is correct? CE=8 and EF=10 and CEF forms a right triangle but how can the hypotenuse be smaller than the other side?

2007-01-25 22:58:46 · answer #2 · answered by aznskillz 2 · 0 0

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