I tried everything but still dont know how to solve it... Plz help
http://s019.radikal.ru/i637/1203/2a/30bd…
http://s019.radikal.ru/i637/1203/2a/30bd…
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If the triangles are similar, then the hypotenuses (hypoteni?) are equal, as are the bottoms; set a proportion and solve:
39/(x+6) = (2x-4)/24
Cross-multiply:
39*24 = (2x-4)(x+6)
936 = 2x^2 + 12x - 4x - 24
936 = 2x^2 + 8x - 24
468 = x^2 + 4x - 12
x^2 + 4x - 480 = 0
(x + 24)(x - 20) = 0
x = -24, 20
Only the positive answer makes sense here, since lengths can't be negative; x = 20.
39/(x+6) = (2x-4)/24
Cross-multiply:
39*24 = (2x-4)(x+6)
936 = 2x^2 + 12x - 4x - 24
936 = 2x^2 + 8x - 24
468 = x^2 + 4x - 12
x^2 + 4x - 480 = 0
(x + 24)(x - 20) = 0
x = -24, 20
Only the positive answer makes sense here, since lengths can't be negative; x = 20.
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You need either SAS or AA and you don't have that from the given info