Question

Question 38 of 165

Solve the system of linear equations below.

2x + y = 5
x + y = 4
x = 1, y = 3
x = 1, y = 5
x = 3, y = 1
x = 9, y = -5

Answer 1

you can subtract the two equations, then the y term will disappear and then you can find x

Answer 2

\[\left[\begin{matrix}2 & 1 \\ 1 & 1\end{matrix}\right]\left[\begin{matrix}x \\ y\end{matrix}\right]=\left[\begin{matrix}5 \\ 4\end{matrix}\right]\]\[|A| = (2 \times 1) - (1 \times 1 ) = 1\]\[A ^{-1} = \left[\begin{matrix}1 & -1 \\ -1 & 2\end{matrix}\right]\]\[\left[\begin{matrix}1 & -1 \\ -1 & 2\end{matrix}\right]\left[\begin{matrix}5 \\ 4\end{matrix}\right]=\left[\begin{matrix}? \\ ?\end{matrix}\right]\]

Answer 3

so....its....

Answer 4

do the matrix multiplication and find out :)

Answer 5

and that is....

Answer 6

answer isnt that important its how you get there

Answer 7

noo im saying whats matrix multiplication

Answer 8

x=1 y=5

Answer 9

im on question 103 now so....