trig
posted by andy .
In a diagram of circle, chords AB and CD
intersect at E. If AE = 3, EB = 4, CE = x, and ED = x  4, what is the
value of x?

you have similar triangles, so set up a ratio
(x4)/4 = 3/x
x^2  4x = 12
x^2  4x  12 = 0
(x6)(x+2)= 0
x = 6 or x = 2, but x = 2 makes no sense
so x = 6