As shown in the figure, △ ABC is an isosceles triangle, ∠ ACB = 90 °, extend AB to F, so that ∠ ECF = 135 °. Verification: AE: EC = Ba: CF

AE:EC=BA: CF.BA?ABEF (collinear) △ ABC is an isosceles triangle, ∠ ACB = 90 ° BC = AC ∠ CBA = 45 ∠ cab = 45 ‰ EAC = 135 ‰ CBF = 135 ‰ EAC = 135 ‰ AEC + ∠ ECA = 180-135 ‰ = 45 ‰ CBF = 135 ‰ BCF + ∠ CFB = 180-135 ‰ = 45 ‰ ECF = 1

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1. The △ ACB is an isosceles triangle, ∠ ACB = 90 ° extend Ba to e, extend AB to F, ∠ ECF = 135 ° Q: is there an equivalent relationship between AB, AE and BF
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