Q. What is the solution to this system of equations?⎩⎨⎧x+3y−z=64x−2y+2z=−106x+z=−12
Write Equations: Write down the system of equations to be solved. \left\{\begin{array}{l}x+3y-z=6,\4x-2y+2z=-10,\6x+z=-12:\end{array}\right. We need to find the values of x, y, and z that satisfy all three equations simultaneously.
Eliminate Variable z: Choose two equations to eliminate one variable. We can start by eliminating z using the first and third equations.First equation: x+3y−z=6Third equation: 6x+z=−12Add the first and third equations to eliminate z:(x+3y−z)+(6x+z)=6−127x+3y=−6
Eliminate Variable z: Now, we need to eliminate the same variable, z, using the second and third equations.Second equation: 4x−2y+2z=−10Third equation: 6x+z=−12To eliminate z, we can multiply the third equation by 2 and then add it to the second equation:(4x−2y+2z)+2∗(6x+z)=−10+2∗(−12)4x−2y+2z+12x+2z=−10−2416x−2y+4z=−34Now, we divide the entire equation by 2 to simplify:z0z1
Two-Variable Equations: We now have two equations with two variables x and y:7x+3y=−68x−y=−17We can multiply the second equation by 3 to align the y terms:3∗(8x−y)=3∗(−17)24x−3y=−51Now we can add this result to the first equation to eliminate y:(7x+3y)+(24x−3y)=−6+(−51)31x=−57Divide both sides by 31 to solve for x:x=−57/31x=−1.8387 (rounded to four decimal places)
Solve for x: Substitute the value of x into one of the two-variable equations to solve for y. We can use the equation 8x−y=−17:8(−1.8387)−y=−17−14.7096−y=−17Add 14.7096 to both sides to solve for y:−y=−17+14.7096−y=−2.2904Multiply both sides by −1:y0 (rounded to four decimal places)
Solve for y: Substitute the values of x and y into one of the original equations to solve for z. We can use the first equation x+3y−z=6: −1.8387+3(2.2904)−z=6−1.8387+6.8712−z=64.0325−z=6Subtract 4.0325 from both sides to solve for z:−z=6−4.0325−z=1.9675Multiply both sides by −1:z=−1.9675 (rounded to four decimal places)