# Live Problems - Stage 3, 4 & 5

Each time students visit the NRICH site there will be some activities which are 'live'. That means we are inviting students to send us their solutions and we will publish a selection of them, along with their name and school's name. If you'd like to know more about what we're looking for, read this short article.

The last day for sending in solutions to these live problems is Monday 6th February.

### Isosceles Triangleslive

##### Age 11 to 14Challenge Level

Draw some isosceles triangles with an area of $9$cm$^2$ and a vertex at (20,20). If all the vertices must have whole number coordinates, how many is it possible to draw?

### Sticky Numberslive

##### Age 11 to 14Challenge Level

Can you arrange the numbers 1 to 17 in a row so that each adjacent pair adds up to a square number?