Question

What is the solution of the system? Use substitution.

x = –2y + 10
–6y = 6x – 6
z = –3x + 10y

A. x = 9, y = –8, z = 114

B. x = –8, y = 9, z = 114

C. x = –8, y = 114, z = 9

D. x = 114, y = 9, z = –8

A, B, C, or D? Please explain (:

Answer 1

use the first equation, the x value is now -2y+10 and use that in the second equation. solve for a and y using just those 2 equations. then plug in the values of x and y in the 3rd eqtion and get z. sorry I can't do it all now. I have 2 exams tomorrow, gotta study more and go to sleep. been studying for almost 8 hours now. bye

Answer 2

x = –2y + 10
–6y = 6x – 6
z = –3x + 10y
2nd line yields: y=-x+1=2y-10+1=2y-9
y=9
x=-18+10=-8

z=-3(-8)+10(9)
24+90=114

answer is B

now bye

Answer 3

alright, thanks a lot. good night (: