Asked by rayne

i need help with this problem
2x+2y+3z=-1
3x-5y-2z=21
7x+3y+5z=10
Answered by Reiny
What method have you learned?
Answered by rayne
EITHER SUBSTITUTION OR ELIMINATION
Answered by Reiny
Ok, elimination then

work on the z's

1st times 2 ---> 4x + 4y + 6z = -2
2nd times 3 ---> 9x - 15y - 6z = 63
add them
13x - 11y = 61 (#4)

2nd times 5 ----> 15x - 25y - 10z = 105
3rd times 2 ----> 14x + 6y + 10z = 20
add them
29x - 19y = 125 (#5)

going to be messy .....
#4 times 19 ----> 247x - 209y = 1159
#5 times 11 ----> 319x - 209y = 1375
subtract them
72x = 216
x = 216/72 = 3 , Yeahhh!
back in #4

13(3) - 11y = 61
-11y = 61-39
-11y = 22
y = -2

back in #1
2(3)+2(-2) + 3z = -1
3z = -1 -2
z = -1

<b> x=3 , y=-2 , z=-1</b>
Answered by rayne
CAN ANYONE JUST GET ME HEADED IN THE RIGHT
DIRECTION ON THIS PROBLEM
2x+2y+3z=-1
3x-5y-2z=21
7x+3y+5z=10
Answered by Reiny
And exactly what did you not like about the solution which is staring at you right above you ?????
There are no AI answers yet. The ability to request AI answers is coming soon!