Question

Can somebody show me how to solve these?
3x+17y+4z=119
2x+3y+15z=87
10x+4y+7z=108

Answer 1

Use elimination.
\[-2(3x+17y+4z=119)\]
\[-6x-34y-8z=-238\]
\[3(2x+3y+15z=87)\]
\[6x+9y+45z=261\]
therefore
-6x-34y-8z=-238
6x+9y+45z=261
when you add them become
-25y+37z=23
do the same thing to the last 2 equations to get rid of the x variable.
multiply a -5 to the second equation.
Find y or z and then solve for x last.