im doing this code and it needs the absolute value of something here is what i have so far.

the formula it gives you is x = absolute value of the square root of radius squared minus the y-intercept squared.

this is the bit of code i have so far and both r and y have been defined.

```
import math
l = abs(math.sqrt(2)(r*r)-(y*y))
```

im getting `TypeError: 'float' object is not callable`

could somebody help me out?