Q. Solve the system of equations by elimination.3x+y−3z=23x−3y−z=−14x−2y+2z=6
Eliminate z from Equations: First, let's eliminate z from the first two equations.3x+y−3z=2 (Equation 1)3x−3y−z=−14 (Equation 2)Multiply Equation 2 by 3 to make the coefficients of z the same.3∗(3x−3y−z)=3∗(−14)9x−9y−3z=−42 (Equation 2 modified)Now, add Equation 1 and Equation 2 modified.(3x+y−3z)+(9x−9y−3z)=2+(−42)12x−8y=−40
Solve for x and y: Next, let's eliminate z from the second and third equations.3x−3y−z=−14 (Equation 2)x−2y+2z=6 (Equation 3) Multiply Equation 3 by −21 to make the coefficients of z the same.−21×(x−2y+2z)=−21×6−21x+y−z=−3 (Equation 3 modified) Now, add Equation 2 and Equation 3 modified.(3x−3y−z)+(−21x+y−z)=−14+(−3)25x−2y=−17
Substitute x and y into Equation: Now, let's solve the system formed by the two new equations we got.12x−8y=−40 (From Step 1)25x−2y=−17 (From Step 2)Multiply the second equation by 4 to make the coefficients of y the same.4∗(25x−2y)=4∗(−17)10x−8y=−68 (Equation 4)Now, subtract Equation 4 from the first new equation.(12x−8y)−(10x−8y)=−40−(−68)2x=28y0
Find z: Substitute x=14 into Equation 4 to find y.10x−8y=−6810(14)−8y=−68140−8y=−68−8y=−68−140−8y=−208y=26
Find z: Substitute x=14 into Equation 4 to find y. 10x−8y=−68 10(14)−8y=−68 140−8y=−68 −8y=−68−140 −8y=−208 y=26Substitute x=14 and y=26 into one of the original equations to find z. x=142 (Equation 3) x=143 x=144 x=145 x=146 x=147 x=148
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