Use the gauss-jordan method to solve the system of equations x+y-5z=-68 2x-y+3z=19 x-2y+2z=-15

Let's solve for x.

xxy−5z=−68

Step 1: Add 5z to both sides.

x2y−5z+5z=−68+5z

x2y=5z−68

Step 2: Divide both sides by y.

x2yy=5z−68y

x2=5z−68y

Step 3: Take square root.

x=√5z−68y or x=−√5z−68y

x=√5z−68y or x=−√5z−68y

Let's solve for x.

2x−y+3z=19

Step 1: Add y to both sides.

2x−y+3z+y=19+y

2x+3z=y+19

Step 2: Add -3z to both sides.

2x+3z+−3z=y+19+−3z

2x=y−3z+19

Step 3: Divide both sides by 2.

2x2=y−3z+192

x=12y+−32z+192

x=12y+−32z+192

Let's solve for x.

x−2y+2z=−15

Step 1: Add 2y to both sides.

x−2y+2z+2y=−15+2y

x+2z=2y−15

Step 2: Add -2z to both sides.

x+2z+−2z=2y−15+−2z

x=2y−2z−15

x=2y−2z−15

It would take her 20 minutes.