1 | initial version |

As John said,

```
sage: f = e^x + x
sage: plot(f, x, -1, 1)
sage: diff(f, x).subs(x=0)
2
sage: f.subs(x=0)
1
sage: g = 2*x + 1
sage: plot(f, x, -2, 2) + plot(g, x, -2, 2, color='red')
![Plot of e^x+x and 2*x+1][1]
```

The line is $y = 2x + 1$.

2 | Images don't work in the code boxes. |

As John said,

```
sage: f = e^x + x
sage: plot(f, x, -1, 1)
sage: diff(f, x).subs(x=0)
2
sage: f.subs(x=0)
1
sage: g = 2*x + 1
sage: plot(f, x, -2, 2) + plot(g, x, -2, 2, color='red')
```~~
![Plot of e^x+x and 2*x+1][1]
~~

The line is $y = 2x + 1$.

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