- #1

- 14

- 0

## Main Question or Discussion Point

I need to graph/find numbers for S∩T where S is x^2+y^2 <=100 and T is x+y<=14.

I know I can find them simply by choosing/picking them, but are there any other solution ?

I thought maybe doing

x^2+y^2 <=100

+

x+y<=14

=

x^2+y^2 + x+y<=14 +100 =

x^2+y^2 + x+y<=114 =

x^2+y^2 <= 114-x-y =

x+y <= sqrt(114-x-y) <-- doesn't work for x=7 and y=7 ???

OR am I doing something wrong ?

Venn diagram confirms that to find an intersection I need to add them and this should yield the result, but this doesn't work ??? why ??

thank you for any responses !:D

I know I can find them simply by choosing/picking them, but are there any other solution ?

I thought maybe doing

x^2+y^2 <=100

+

x+y<=14

=

x^2+y^2 + x+y<=14 +100 =

x^2+y^2 + x+y<=114 =

x^2+y^2 <= 114-x-y =

x+y <= sqrt(114-x-y) <-- doesn't work for x=7 and y=7 ???

OR am I doing something wrong ?

Venn diagram confirms that to find an intersection I need to add them and this should yield the result, but this doesn't work ??? why ??

thank you for any responses !:D