dat <- structure(list(x = c(1, 2, 3, 4, 5), y = c(8, 12, 22, 28, 30)), .Names = c("x", "y"), row.names = c(NA, -5L), class = "data.frame")

summary(dat$x)
summary(dat$y)



fm1 <- lm(dat$y ~ dat$x, data = dat)
fm1



fm2 <- lm(dat$x ~ dat$y, data = dat)
fm2


fm1_m <- fm1$coefficients[1]
fm1_q <- fm1$coefficients[2]

fm2_m <- fm2$coefficients[1]
fm2_q <- fm2$coefficients[2]


xx <- 1:5
yy <- 8:30

convyval <- function(e){(1/fm2_q)*e - (fm2_q/fm2_m)}


# PREDICT VALUES
yhat1 <- predict(fm1, list(x = xx))

yhat2 <- convyval(yy)


# PLOT DATA
plot(dat$x,dat$y)

lines(xx, yhat1, col="blue", lwd=2)
lines(xx, yhat2, col="red", lwd=2)