x + y = 12
x - y = 10

What is the value of the x-determinant for the system shown?

-22
-12

Question

x + y = 12
x - y = 10

What is the value of the x-determinant for the system shown?


-22
-12 <-- i chose this!
-2

kc_kennylau · Answer

$$Dx=\left|\begin{array}{cc}12&1\10&-1\end{array}\right|=12\times-1-1\times10=-12-10=-22$$

ttop0816 · Answer

@kc_kennylau  oh thank you so much!

kc_kennylau · Answer

@ttop0816 no problem at all :)

ttop0816 · Answer

@kc_kennylau  yay im your 100th fan! congrats (:

kc_kennylau · Answer

wow :DDDDDD

kc_kennylau · Answer

anonymous · Answer

x+y=12
x-y=10

x=12-y

12-y-y=10
-2y+12=10
-2y=10-12
-2y=-2
y=1


x=12-y
x=12-1
x=11

S={11,1}

loser66 · Answer

@mire but the question is about x determinant , not x. They apply Cramer's rule to have it and they are correct.