Question

In triangle ABC angle B is equal to 90 degree and BD is perpendicular to AC .if AC isequal to 9 cm and AD is equal to 3 cm then find BD

Answer 1

Answer:

BD=6 CM

Explanation:

In Δ ABC,

∠B=90°

SEE FIGURE GIVEN IN THE LAST

By Pythagoras Theorem,

AC=9 cm

AD=3 cm

AC²=AB²+BC²

9²=AB²+BC²

AB²=9²-BC²

AB²=81-BC²

In Δ ABD,

∠D=90°

By Pythagoras Theorem,

AB²=AD²+BD²

BD²=AB²-AD²

BD²=81-BD²-AD²

BD²+BD²=81-AD²

2BD²=81-AD²

Given That AD=3 CM

So,

2BD²=81-3²

2BD²=81-9

2BD²=72

BD²=72/2

BD²=36

BD=√36

BD=6 CM

Hope its Helpfull to You,

Thanking You

Answer 2

Answer:

AC = 9

AD = 3

CD = 9-3 = 6cm

∆ABD ~ ∆BDC

CD \ BD = BD \ AD

BD² = AD x CD

BD² = 3 × 6

BD² = 18

BD = √18

BD = 3√2 ans

BD = 3√2 it's your ans

I hope you will understand ❤️