The interior angles of a triangle are

**mudskipper** · 28 April 2012, 19:03

Originally posted by BrilloPad View Post

The interior angles of a triangle are :-

5x+3y
3x+20
10y+30

What is x+y?

x=0, y=10, x+y = 10

**TimberWolf** · 28 April 2012, 19:09

Originally posted by BrilloPad View Post

The interior angles of a triangle are :-

5x+3y
3x+20
10y+30

What is x+y?

Are x and y meant to be integers? If so, x + y = 15 works.

Where x = 13, y = 2

**centurian** · 28 April 2012, 19:12

42

HTH

**OwlHoot** · 28 April 2012, 19:53

Originally posted by BrilloPad View Post

The interior angles of a triangle are :-

5x+3y
3x+20
10y+30

What is x+y?

Is the triangle in a space of negative, zero, or positive curvature ?

**BrilloPad** · 29 April 2012, 06:10

Originally posted by TimberWolf View Post

Are x and y meant to be integers? If so, x + y = 15 works.

Where x = 13, y = 2

Originally posted by k2p2 View Post

x=0, y=10, x+y = 10

Question came from a maths quiz set nationally for children up to year 8. My daughter got set it although being only in year 5!

I have sent k2p2's answer to the organizers - the official answer is TimberWolf's.

I thought it was a great question as you can get to 8x+13y=130 quite easily. But beyond that it requires some thinking.

**NotAllThere** · 29 April 2012, 06:15

That gives a whole other range of answers

Assuming positive curvature, 8x + 13y + 50 >= 180.
Negative curvature, 8x + 13y + 50 <=180
No curvature, 8x + 13y = 130.

x and y can take any value you like and one of these will be true.

**BrilloPad** · 29 April 2012, 06:18

I just double checked the question - no mention of flat space. But it does say that x and y have to be positive integers.

**Diver** · 29 April 2012, 06:33

Originally posted by BrilloPad View Post

I just double checked the question - no mention of flat space. But it does say that x and y have to be positive integers.

Would the answer be one of the following;

A 15
B 14
C 13
D 12
E 11

**mudskipper** · 29 April 2012, 06:52

Originally posted by Diver View Post

Would this be the question in the;

UK JUNIOR MATHEMATICAL CHALLENGE
THURSDAY 26th APRIL 2012
Organised by the United Kingdom Mathematics Trust
from the School of Mathematics, University of Leeds

Question 25

The interior angles of a triangle are (5x  3y) ,
 (3x  20) and  (10y  30) , where x, y are
positive integers.
What is the value of x  y ?

A 15 B 14 C 13 D 12 E 11

So, given the full question, my answer is invalid.

The interior angles of a triangle are