help me please :( :( :(

solve the system by elimination

x + 5y - 4z = -10
2x - y + 5z = -9
2x - 10y - 5z = 0

1. (5, -1, 0)
2. (-5, 1, 0)
3. (-5, -1. 0)
4. (-5, -1, -2)

Question

help me please :( :( :(

solve the system by elimination

 x + 5y - 4z = -10
2x - y + 5z = -9 
2x - 10y - 5z = 0

1. (5, -1, 0)
2. (-5, 1, 0) 
3. (-5, -1. 0)
4. (-5, -1, -2)

anonymous · Answer

set al the acquation =0 than subtract al the acqations zo that one or two variable = 0 and sovle left over the vartiable

anonymous · Answer

can you help me do that?

anonymous · Answer

10 + 1x + 5y - 4z = 0
  9 + 2x - 1y + 5z = 0
  0 + 2x - 10y - 5z =0

anonymous · Answer

Do i put this in slope intercept form? idk where to put the z though

anonymous · Answer

multiply equations so when you withdraw al the equations, you wil be left with one variable

anonymous · Answer

im still confused.. do i have to graph these too to get those points?

anonymous · Answer

are you sure it is 2x both times? not one 2x and one -2x? that will make the question a lot easier

hero · Answer

Pair the 1st Equation with the 2nd Equation
x + 5y - 4z = -10
2x - y + 5z = -9 

Pair the 2nd Equation with the 3rd Equation
2x - y + 5z = -9 
2x - 10y - 5z = 0

Eliminate the same variable in both, preferably z. Afterwards, you're left with a system of two equations of variables x and y...which you should be able to solve.

hero · Answer

@hellothere2

anonymous · Answer

is it  (-5, 1, 0)  @Hero

hero · Answer

Did you set up the system in accordance with my suggestion?

hero · Answer

Of course, the easiest way to solve this would have been to just plug the points.

hero · Answer

(-5,1,0) can't be it because it fails for the first equation:
x + 5y - 4z = -10
-5 + 5(1) -4(0) = -10
-5 + 5 - 0 = -10
0 = -10

False

hero · Answer

If they give you the points, keep plugging in until you find the right point.

anonymous · Answer

so -5, -1, 0? or -5, -1, 2?

hero · Answer

I suppose you're going to keep guessing until I say which one is correct. If you actually try doing the problem, you'll be able to figure out which one is correct on your own.

anonymous · Answer

i plugged it in and i do believe it is (-5, -1, 0)

anonymous · Answer

@Hero

hero · Answer

Very good

anonymous · Answer

thanks for helping me set it up, i knew they were both negatives thats why i asked

hero · Answer

If they don't give you any possible points, then you can try the other method I suggested