As shown in the figure, in the triangle ABC, the angle BAC is equal to 90 degrees, ad is perpendicular to BC, and BD square = BD times BC

As shown in the figure, in the triangle ABC, the angle BAC is equal to 90 degrees, ad is perpendicular to BC, and BD square = BD times BC

The problem is wrong, should be ba square = BD times BC
Because △ BDA is similar to △ BAC, BA / BC = BD / BA
Diagonal multiplication, so the square of Ba = BD times BC
This is a very important theorem~