Q. Solve the system of equations by elimination.3x−y−z=7−2x+y+3z=−72x−2y+z=14
Eliminate y by adding equations: First, let's add the first and second equations to eliminate y.(3x−y−z)+(−2x+y+3z)=7+(−7)3x−y−z−2x+y+3z=0x+2z=0
Simplify third equation: Now, let's multiply the third equation by 21 to simplify it.(21)(2x−2y+z)=(21)(14)x−y+(21)z=7
Eliminate y by adding equations: Next, we'll add the modified third equation to the first equation to eliminate y. (x−y+(1/2)z)+(3x−y−z)=7+7x−y+(1/2)z+3x−y−z=144x−2y−(1/2)z=14
Eliminate z by adding equations: We can now add the new equation from the previous step to the modified second equation to eliminate z.(4x−2y−21z)+(x+2z)=14+04x−2y−21z+x+2z=145x−2y+23z=14
Get rid of fraction: Let's multiply the new equation by 2 to get rid of the fraction.2(5x−2y+23z)=2(14)10x−4y+3z=28
Eliminate y by adding equations: Now, we'll add the modified third equation to the new equation to eliminate y.(10x−4y+3z)+(x−y+21z)=28+710x−4y+3z+x−y+21z=3511x−5y+27z=35
Solve for x: We can now solve for x by adding the first and third equations.(3x−y−z)+(11x−5y+27z)=7+353x−y−z+11x−5y+27z=4214x−6y+25z=42
Divide to solve for x: Divide the new equation by 14 to solve for x. (14x−6y+(5/2)z)/14=42/14 x−(6/14)y+(5/28)z=3 x=3+(6/14)y−(5/28)z
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