Question

Help!!!! What is the solution of the system of equations?

Answer 1

Are you supposed to use a certain method?

Answer 2

no idea, we haven't done any questions like this and that's all it tells me. I have the options of either no solution, (5,-2,7), (-5,2,7), or (5,2,-7)

Answer 3

I would user the elimination method. This is a method where you add or subtract the given equations eliminating a variable until you get a solution.

Answer 4

In this case I would take equation 1 and add it to equation 3 after multiplying equation 3 through by a -2. Like this:
-3x -4y - 3z = -7
-10x +4y -10z=-18 (equation 3 multiplied by -2)
----------------- adding
-13x -13z=-25 Eliminated the y variable. do you follow with understanding?

Answer 5

yeah

Answer 6

In a similar fashion I would take the 2nd equation and add it to the 3rd equation after multiplying the 3rd equation by -3. Like this;
2x - 6y + 2z = 3 (2nd equation)
-15x + 6y - 15z = -27 (3rd equation multiplied by -3)
----------------- add
-13x -13z = -24

Now note that we now have developed two equations:
-13x - 13y =-25
-13x - 13y =-24
Note they are inconsistent They should equal the same thing as the left side of each are identical.

You can say no solution, and you can prove that by other three choices by substituting the values provided in all three equations.

Answer 7

The other three options will not even work in equation 1
-3x -4y -3z = -7
-3(5) -4(-2) -3(7) =-7
-15 + 8 -21 = -7
-28 = -7 NO and so on.

Answer 8

ohhhh okay. wow. thank you for explaining it so well