According to the question:
a m = 6； b n = 8； c n = 10； I
△ The area of △CBD is:
(b+c) (m+n)1/2 = (3+4+5)+an1/2 is multiplied by 2 on both sides.
Three formulas of (b+c) (m+n) = 24+a n into I
(8/n+ 10/n) (m+n)=24+(6/m) n
(18/n) (m+n) = 24+6 n/m, multiply both sides of the equal sign by mn/6, and get it after sorting.
3m (m+n) = 4mn+n 2 rearrangement
3m^2-mn-n^2=0
Get this binary quadratic equation, solve it to get the values of m and n, and then bring the value of m into the first formula in I to get the value of a, so that the bottom EF of △AEF and its height n are obtained, and the area is solved.