Add and edit report.Rmd

Below is a scatter plot with the regression line.

```{r plot, fig.height=5}

par(mar = c(4, 4, 1, 1))

plot(regFormula(), data = mtcars, pch = 19, col = 'black', alpha=0.8)

abline(fit, col = 'gray', lwd = 2)

```

Here is my regression model:

```{r model, collapse=TRUE}

options(digits = 4)

fit <- lm(regFormula(), data = mtcars)

b   <- coef(fit)

summary(fit)

```

The fitting result is $mpg = `r b[1]` + `r b[2]``r input$x`$.