Q. Solve the system of equations by substitution.2x−2y−2z=2x=7−3x+3y+z=−9
Substitute x=7: First, let's substitute x=7 into the other two equations.2(7)−2y−2z=2−3(7)+3y+z=−9
Simplify equations: Now, let's simplify both equations.14−2y−2z=2−21+3y+z=−9
Solve for y in first equation: Next, we'll solve the first equation for y. 14−2y−2z=2−2y−2z=2−14−2y−2z=−12
Divide by −2 for y: Divide the whole equation by −2 to solve for y.y+z=6
Solve for y in second equation: Now, let's solve the second equation for y.−21+3y+z=−93y+z=−9+213y+z=12
Divide by 3 for y: Divide the whole equation by 3 to solve for y.y+3z=4Oops, this step contains a mistake. We should not divide z by 3 when dividing the whole equation by 3.
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