Question

Use Cramer's rule to solve the system. 2x + 4y - z = 32 x - 2y + 2z = -5 5x + y + z = 20
A. {( 1, -9, -6)}
B. {( 2, 7, 6)}
C. {( 9, 6, 9)}
D. {( 1, 9, 6)}

d ?

Answer 1

+2 +4 -1
+1 -2 +2 ---> -4+40-1 -10-4-4 = 17 yuuk
+5 +1 +1

now solve for Y not x because your solutions set has all different y values :)

+2 32 -1
+1 -5 +2 ---> --10+320-20 -25-80-32 = 153
+5 20 +1
then
153/17 = ( whew, D

Answer 2

I mean 9 :)

Answer 3

SO I'm right ? :)

Answer 4

Yes, it's D.
Though it's hard to show 3x3 Cramer's rule here. ;u;

Answer 5

Thanks !