Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

#1 2017-07-13 14:23:34

Bhavya2
Guest

Area of triangle

In right triangle BAC , A is a right angle. AD is perpendicular to BC.

If BD = 9 cm and DC = 4 cm , can you find the area of triangle ABC.
If yes what is the area
If no why can't we find it out?

#2 2017-07-13 15:59:18

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 798

Re: Area of triangle

The area is 39 cm² because AD is 6 cm.

Offline

#3 2017-07-13 19:20:52

bob bundy
Registered: 2010-06-20
Posts: 8,054

Re: Area of triangle

hi Bhavya2

Welcome to the forum.

I have deleted my answer because it was wrong.  Monox D. I-Fly has the right result.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

Offline

#4 2017-07-13 21:02:23

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 798

Re: Area of triangle

bob bundy wrote:

Monox D. I-Fly: Where did you get 6 from?

Offline

#5 2017-07-13 22:04:40

bob bundy
Registered: 2010-06-20
Posts: 8,054

Re: Area of triangle

hi Monox D. I-Fly

Thanks for the explanation.  My answer is completely wrong so I have deleted it. Whoops.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

Offline

#6 2017-07-14 02:52:14

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 798

You are welcome.

Offline

#7 2017-07-15 19:24:51

bob bundy
Registered: 2010-06-20
Posts: 8,054

Re: Area of triangle

hi NakulG

19.5? What, the area?  I think not.

Monox D. I-Fly wrote:

The area is 39 cm² because AD is 6 cm.

This is correct.  half base times height = 0.5 x (9+4) x 6 = 13 x 3 = 39.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

Offline