Question

如图,在△ABC中,∠C=90°,BD=1,AD=5,AB=根号34,求AC长

Answer 1

BD^2=BC^2+CD^2=1,BC^2=1-CD^2

AC^2=AB^2-BC^2,AC=AD+CD

(AD+CD)^2=AB^2-BC^2

(5+CD)^2=34-1+CD^2

10CD=8

CD=0.8

AC=AD+CD=5+0.8=5.8