解:设滑道$AC$的长为$x\ \mathrm {m}$
由题意得$AE = AC = x\ \mathrm {m},$$∠ABC = 90°$
又$BE = 1\ \mathrm {m},$∴$AB = AE - BE = (x - 1)m$
在$Rt\triangle ABC$中,$BC = 5\ \mathrm {m}$
由勾股定理,得$AB^2+BC^2=AC^2$
∴$(x - 1)^2+5^2=x^2,$解得$x = 13$
则滑道$AC$的长为$13\ \mathrm {m}$