Question

I need the answer.Help me out

Answer 1

The answer is
`\boxed{7},` where
`a=5` and
`b=2.`

Solution sketch:

Apply the Pythagorean theorem to find
`EC` and
`AE,` which you then use to find
`AD` and
`BC.` Apply Heron's formula to
`\triangle ABC` to find that its area is 10, and then use
`[ABC]=((AB)(CF))/(2)` (base times height over 2) to finish by solving for
`CF.`.