Question

resuelve esto por el método de Cramer
4x + 5y = 5
-4x - 10y = -7



3x - y = 1
2x + 3y = 8​

Answer 1

Respuesta:

x = 3/4  ; y = 2/5

------------------------

x = 1   ; y = 2

Explicación paso a paso:

4x + 5y = 5

-4x - 10y = -7

Δ S=      $\left[\begin{array}{ccc}4&5\\-4&-10\end{array}\right]$  = (4) (-10) - (5) (-4) = -20

Δ x =  $\left[\begin{array}{ccc}5&5\\-7&-10\end{array}\right]$ = (5)(-10) - (-7) (5) = -15

Δ y =  $\left[\begin{array}{ccc}4&5\\-4&-7\end{array}\right]$ = (4)(-7) - (-4) (5) = -8

x = Δ x / Δ S = -15 / -20 = 3/4    ;  x = 3/4

y = Δ y / Δ S = -8/ -20 = 2/5      ;  y = 2/5

------------------------------------------------------------------

3x - y = 1

2x + 3y = 8

Δ S=      $\left[\begin{array}{ccc}3&-1\\2&3\end{array}\right]$  = (3) (3) - (2) (-1) = 11

Δ x =  $\left[\begin{array}{ccc}1&-1\\8&3\end{array}\right]$ = (1)(3) - (8) (-1) = 11

Δ y =  $\left[\begin{array}{ccc}3&1\\2&8\end{array}\right]$ = (3)(8) - (2) (1) = 22

x = Δ x / Δ S = 11 / 11 = 1    ;  x = 1

y = Δ y / Δ S = 22/ 11 = 2  ;  y = 2