Question

By what factor would you need to multiply the first and second equations to eliminate x? By what factor would you need to multiply the second and third equations to eliminate x?

Answer 1

Multiply the first equation by -2 and the third equation by -6.

Explanation:

Combine the first and second equations to eliminate x.

Multiply the first equation by -2:

-12x-12y-12z=-39

Add this to the second equation:

(-12x-12y-12z)+(12x+2y+z)=-39+9.5

-10y-11z= -29.5

10y+11z=29.5

Combine the second and third equations to eliminate x:

Multiply the third equation by -6:

-12x-24y-30z=-84

(12x-24y-30z)+(12x+2y+z)= -84+9.5

-22y-29z=-74.5

22y+29z= 74.5

Answer 2

equation 1 : x + y + z = 3.25
equation 2 : 12x + 2y + z = 9.50
equation 3 : 2x + 4y + 5z = ??

u would multiply equation 1 by -12.....take that result and add it to equation 2....this eliminates x.

u would multiply equation 3 by -6...take that result and add it to equation 2....this eliminates x