# triangle Question

• Jun 9th 2006, 05:16 AM
DebfromOZ
triangle Question
Hi, my daughter has a question I can't help her with...

There is a right-angled triangle, base is 10cm plus 6cm, side is 12 cm, hypotenuese is unknown, there is a line about two-thirds (at the 10 and 6) of the way from top to bottom which is x. She needs to work out x, the answer is 7.5cm but we don't know how to get that answer.

thanks a lo :eek: t
Deb
• Jun 9th 2006, 05:46 AM
CaptainBlack
Quote:

Originally Posted by DebfromOZ
Hi, my daughter has a question I can't help her with...

There is a right-angled triangle, base is 10cm plus 6cm, side is 12 cm, hypotenuese is unknown, there is a line about two-thirds (at the 10 and 6) of the way from top to bottom which is x. She needs to work out x, the answer is 7.5cm but we don't know how to get that answer.

thanks a lo :eek: t
Deb

I hope this is what you need (well turned on its side anyway :o ):
• Jun 9th 2006, 06:13 AM
Soroban
Hello, Deb!

I think I've interpreted the problem correctly . . .

Quote:

There is a right-angled triangle, base is 10cm plus 6cm, side is 12 cm, hypotenuese is unknown.
There is a line about two-thirds (at the 10 and 6) of the way from top to bottom which is x.
She needs to work out x.
The answer is 7.5cm but we don't know how to get that answer.
Not sure what you mean by "about two-thirds of the way from top to bottom".
But here's my diagram.
Code:

      *       |  *       |      *       |          *   12 |          |  *    x       |          |      *       |          |          *       * - - - - - * - - - - - - - *             10            6
Using Pythagorus: . $hyp^2 = 12^2 + 16^2 = 400\quad\Rightarrow\quad hyp = 20$

From the similar right triangles: . $\frac{x}{6} = \frac{20}{16}\quad\Rightarrow\quad x = 7.5$
• Jun 9th 2006, 06:37 AM
DebfromOZ
triangle Question
Thanks for your efforts to help, I should have explained it a bit better. The 10 is at the 'pointy' end of the triangle and the 6 at the right angle end of the triangle. The x is the vertical line form the top to the bottom, as in the first response, not on the hyp. I think it's something to do with similar triangles and the ratio factor from what I've been reading.

Thanks anyway, it's time for bed in Australia, so I'll look again in the morning!

Deb
• Jun 9th 2006, 06:42 AM
DebfromOZ
triangle Question
I just realised that Captain Black's answer works if I swap around the 10 and 6. So thank you!

Deb
• Jun 9th 2006, 07:02 AM
CaptainBlack
Quote:

Originally Posted by DebfromOZ
I just realised that Captain Black's answer works if I swap around the 10 and 6. So thank you!

Deb