Q. Solve the system of equations by elimination.2x−3y−z=13x+3y−2z=−12−2x−y−2z=16
Eliminate x by adding equations: Add the first and third equations to eliminate x. (2x−3y−z)+(−2x−y−2z)=1+16 2x−3y−z−2x−y−2z=17 −4y−3z=17
Eliminate x by multiplying and adding equations: Multiply the second equation by 2 and add it to the third equation to eliminate x. (2×(3x+3y−2z))+(−2x−y−2z)=2×(−12)+16 6x+6y−4z−2x−y−2z=−24+16 4x+5y−6z=−8
Solve for y from new equations: Now we have two new equations:−4y−3z=174x+5y−6z=−8Let's solve for y from the first new equation.−4y=17+3zy=−417+3z
Substitute y in second new equation: Substitute y in the second new equation.4x+5(−417+3z)−6z=−84x−(485+415z)−6z=−84x−485−415z−424z=−84x−485−439z=−8
Clear fractions by multiplying: Multiply everything by 4 to clear the fractions.4×(4x−485−439z)=4×(−8)16x−85−39z=−32
Solve for x from first equation: Add 85 to both sides.16x−39z=−32+8516x−39z=53
Substitute x in original equation: Now we have two equations with two variables:16x−39z=53−4y−3z=17Let's solve for x from the first equation.16x=53+39zx=1653+39z
Clear fractions by multiplying: Substitute x in the first original equation.2(1653+39z)−3y−z=116106+78z−3y−z=1
Combine like terms: Multiply everything by 16 to clear the fractions.16×(16106+78z)−16×(3y)−16×(z)=16×(1)106+78z−48y−16z=16
Solve for z from second equation: Combine like terms.106+62z−48y=16
Substitute z in equation: Subtract 106 from both sides.62z−48y=16−10662z−48y=−90
Clear fractions by multiplying: Now we have two equations with two variables:62z−48y=−90−4y−3z=17Let's solve for z from the second equation.−3z=17+4yz=−317+4y
Distribute −62: Substitute z in the equation 62z−48y=−90.62(−317+4y)−48y=−90−62(17+4y)/3−48y=−90
Combine like terms: Multiply everything by 3 to clear the fractions.3×(−62(17+4y)/3)−3×(48y)=3×(−90)−62(17+4y)−144y=−270
Solve for y: Distribute −62. −62×17−62×4y−144y=−270 −1054−248y−144y=−270
Substitute y in equation: Combine like terms.−1054−392y=−270
Solve for z: Add 1054 to both sides.−392y=−270+1054−392y=784
Substitute z in equation: Divide by −392 to solve for y.y=−392784y=−2
Substitute z in equation: Substitute y back into the equation z=−317+4y.z=−317+4(−2)z=−317−8z=−39z=−3
Substitute z in equation: Substitute y back into the equation z=−317+4y. z=−317+4(−2) z=−317−8 z=−39 z=−3Substitute z back into the equation x=1653+39z. x=1653+39(−3) y0 y1 y2
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