Respuesta :
Answer: a-b+c+d =4
Step-by-step explanation:
The given system of equation is
[tex]2x+8y=7\\4x-2y=9[/tex]
from this we have the following matrices
[tex]A_1 =\begin{bmatrix}\\2 &8 \\ \\4&2 \\\end{bmatrix}\ ,X=\begin{bmatrix}\\x\\ \\y\\\end{bmatrix}\text{and}\ C=\begin{bmatrix}\\7\\ \\9\\\end{bmatrix}[/tex]
the given matrix A =[tex]\begin{bmatrix}\\a &c \\ \\b &d \\\end{bmatrix}[/tex]
On comparing Matrix [tex]A_1[/tex] with Matrix A
[tex]\begin{bmatrix}\\a &c \\ \\b &d \\\end{bmatrix}=\begin{bmatrix}\\2&8 \\ \\4 &-2 \\\end{bmatrix}[/tex]
we have the following values
a=2 ,b=4,c=8,d=-2
Thus a-b+c+d =2-4+8+(-2)=4