[R] Further questions

[CHATTON Anne]

Hi R folks,
In my previous post I forgot to mention that I was new to R. I was really grateful for your quick help. I have two further questions:
1) In the graph of a regression line I would like to show one specific residual yi obs - yi pred (let's take the person whose residual is 76). How do I add a bracket to this vertical distance and name it? I'am getting stuck after the "textxy" function.
Age <- c(39, 47, 45, 47, 65, 46, 67, 42, 67, 56, 64, 56, 59, 34, 42, 48, 45, 
17, 20, 19, 36, 50, 39, 21, 44, 53, 63, 29, 25, 69)
BloodPressure <- c(144, 220, 138, 145, 162, 142, 170, 124, 158, 154, 162, 
150, 140, 110, 128, 130, 135, 114, 116, 124, 136, 142, 120, 120, 160, 158, 
144, 130, 125, 175)
mean(Age)
mean(BloodPressure)
SimpleLinearReg1 <- lm(BloodPressure ~ Age)
summary(SimpleLinearReg1)
coeff <-coefficients(SimpleLinearReg1)
coeff
eq <- as.formula(
  paste0("y ~ ", round(coefficients(SimpleLinearReg1)[1],2), "", 
    paste(sprintf(" %+.2f*%s ", 
                  coefficients(SimpleLinearReg1)[-1],  
                  names(coefficients(SimpleLinearReg1)[-1])), 
          collapse="")))
eq <- paste0("y = ", round(coeff[2],1), "x + ", round(coeff[1],1))
plot(Age, BloodPressure, pch = 16, cex = 1.3, col = "blue", 
main = "Graphe de la relation entre l'âge et la pression artérielle", 
xlab = "Age (année)", ylab = "Pression artérielle (mmHg)")
abline(SimpleLinearReg1, col="red")
res <- signif(residuals(SimpleLinearReg1), 2)
pre <- predict(SimpleLinearReg1) 
segments(Age, BloodPressure, Age, pre, col="red")
library(calibrate)
textxy(Age, BloodPressure, res, cex=0.7) 2) 

2) I also need your help plotting a hyperplan for a multiple regression and here I am really stuck...
inc <- c(25000, 28000, 17500, 30000, 25000, 32000, 30000, 29000, 26000, 40000)
age <- c(60, 36, 21, 35, 33, 43, 29, 45, 41, 48)
educ <- c(12, 12, 13, 16, 16, 12, 13, 15, 15, 20)
MultLinearReg1 <- lm(inc ~ age + educ)
summary(MultLinearReg1)

Thank you so much!