Q. Solve the system of equations by substitution.−x−2y−2z=33x+2y+z=−12z=7
Substitute z=7: Substitute z=7 into the first equation −x−2y−2z=3. −x−2y−2×7=3 −x−2y−14=3 −x−2y=17
Solve for x: Now, let's solve for x.x=−2y−17
Substitute z=7: Substitute z=7 into the second equation 3x+2y+z=−12.3x+2y+7=−123x+2y=−19
Solve for y: Now substitute x from the first modified equation into the second modified equation.3(−2y−17)+2y=−19−6y−51+2y=−19−4y−51=−19
Find x: Solve for y.−4y=32y=−8
Final Solution: Now we have y, let's find x using x=−2y−17. x=−2(−8)−17 x=16−17 x=−1
Final Solution: Now we have y, let's find x using x=−2y−17. x=−2(−8)−17 x=16−17 x=−1We have x and y, and we know z=7 from the start. So the solution is (x,y,z)=(−1,−8,7).
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