In this figure, (similar triangles) DE is parallel to AC, AD=CE=4,BD=BE=1, and AC=7. Find the length of DE to the nearest tenth of a unit.
To solve this problem, we can use the properties of similar triangles.
Since DE is parallel to AC, we can see that triangles ADE and CBE are similar. We know that AD = CE = 4, BD = BE = 1, and AC = 7.
We can set up a proportion to find the length of DE:
(AD)/(BD) = (CE)/(BE) = (AC)/(DE)
Substitute the given values into the proportion:
4/1 = 7/DE
Cross multiply to solve for DE:
4 * DE = 7
DE = 7/4
DE = 1.75
Therefore, the length of DE is 1.75 units.