library(matlib)
C <- matrix(c(-4,5,7,-9,6,1,9,2,8), nrow = 3, ncol = 3)
d <- c(1, 5, 4)
C
##      [,1] [,2] [,3]
## [1,]   -4   -9    9
## [2,]    5    6    2
## [3,]    7    1    8
d
## [1] 1 5 4
Solve(C,d)
## x1      =  -0.57597173 
##   x2    =   1.02120141 
##     x3  =   0.87632509
plotEqn3d(C,d)
plotEqn3d
## function (A, b, vars, xlim = c(-2, 2), ylim = c(-2, 2), zlim, 
##     col = 2:(nrow(A) + 1), alpha = 0.9, labels = FALSE, solution = TRUE, 
##     axes = TRUE, lit = FALSE) 
## {
##     if (!is.numeric(A) || !is.matrix(A)) 
##         stop("A must be a numeric matrix")
##     if (missing(b)) {
##         b <- A[, ncol(A)]
##         A <- A[, -ncol(A)]
##     }
##     if (ncol(A) != 3) 
##         stop("plotEqn3d only handles three-variable equations")
##     if (missing(vars)) 
##         vars <- paste0("x", 1:ncol(A))
##     neq <- nrow(A)
##     if (missing(zlim)) {
##         x <- xlim
##         y <- ylim
##         zlim <- c(0, 0)
##         for (i in 1:neq) {
##             if (A[i, 3] != 0) {
##                 z <- (b[i] - A[i, 1] * x - A[i, 2] * y)/A[i, 
##                   3]
##                 zlim <- range(c(zlim, z))
##             }
##         }
##     }
##     if (length(col) < neq) 
##         col <- rep_len(col, length.out = neq)
##     if (is.logical(labels) && labels) {
##         labels <- paste0("(", 1:neq, ")")
##     }
##     else labels = NULL
##     depth_mask <- if (alpha < 1) 
##         TRUE
##     else FALSE
##     dat <- replicate(2, 1:3)
##     rgl::plot3d(dat, type = "n", xlim = xlim, ylim = ylim, zlim = c(-3, 
##         3), xlab = vars[1], ylab = vars[2], zlab = vars[3], axes = axes)
##     rgl::planes3d(A[, 1], A[, 2], A[, 3], -b, col = col, alpha = alpha, 
##         lit = lit, depth_mask = depth_mask)
##     if (solution) {
##         x <- try(solve(A, b), silent = TRUE)
##         if (!inherits(x, "try-error")) 
##             rgl::spheres3d(solve(A, b), radius = 0.2)
##     }
## }
## <bytecode: 0x000001a6891a5b00>
## <environment: namespace:matlib>

Sistem geometri visual adalah suatu metode yang digunakan untuk mempresentasikan dan memanipulasi objek geometri secara visual