# solve[ ]

solve \[ \] function

# solve a*x + b = 0

```
sol =  solve[ a*x + b == 0, {x}];

show sol;

save as solve4;
```

Output

"sol" → {-(b/a)}

# solve a*x +b == 0 for x

```
sol =  solve a*x +b == 0 for x;

show sol;

save as solve4;
```

Output

"sol" → {-(b/a)}

# instance [ ]

```
radius=norm[{x,y}];
linear = 3*x+2*y;

pts = instance [linear <= 3 and 0.5<=radius <=1 , 300];

//show pts;
pointplot pts;

save as cropped_anulus;
```

Ouput

[![instance_annulus.png](https://wiki.compclassnotes.com/uploads/images/gallery/2026-05/scaled-1680-/instance-annulus.png)](https://wiki.compclassnotes.com/uploads/images/gallery/2026-05/scaled-1680-/instance-annulus.png)