Need asap will mark ! what is the solution to the system of equations -4x - 5y - z = 18 -2x - 5y -2z=12 -2x + 5y +2z=4 a) (4,0,2) b) (-4,0,-2) c) (-4,2,0) d) (-4,0,2)

B

Step-by-step explanation:

When we have multiple answers, we can check each to find the solution. Each ordered pair is written as (x,y,z). We substitute each into the equations to find which satisfy all equations and which do not.

A) (4,0,2)

-4(4)-5(0)-(2)=18

-16-0-2=18

Not a solution

B) (-4,0,-2)

-4(-4)-5(0)-(-2)=18

16-0+2=18

18=18 is true. We now try the other equations.

-2(-4)-5(0)-2(-2)=12

8-0+4=12

12=12

We try the last equation.

-2(-4)+5(0)+2(-2)=4

8+0+-4=4

4=4

We no longer need to try C or D because a system of equations only has one solution. B is the solution.

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step-by-step explanation:

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