3 Variable Systems

How would you know a system has no solution?

• You end up with 0=0 at some point.

• The value of one of the variables is 0 (i.e. x=0, y=0, or z=0).

• You end up with a false statement (e.g. 3=5) at some point.

• You end up with fractions at some point.

Tags

CCSS.8.EE.C.8B

Say you wanted to eliminate x from the system shown. How would you do it?

• Add the equations without doing any multiplication.

• Multiply the first equation by 2 and the second equation by 3, then add the equations.

• Multiply the first equation by negative 2 and the second equation by 3, then add the equations.

• Multiply the first equation by 3 and the second equation by negative 2, then add the equations.

Tags

CCSS.HSA.REI.C.6

CCSS.8.EE.C.8B

Which of the following could be a correct first step in solving the system shown? Select all that apply.

• Multiply the first equation by 2, then add the result to the third equation.

• Multiply the second equation by 2, then add the result to the third equation.

• Add the first and second equation.

• Add the first and third equation.

• Add the second and third equation.

Tags

CCSS.HSA.REI.C.6

CCSS.HSA.REI.C.5

True or false: (2,1,-1) is the solution to the system

• True

• False

Tags

CCSS.HSA.REI.C.6

Solve the system using elimination.

Tags

CCSS.HSA.REI.C.6

CCSS.HSA.REI.C.5

Solve the system using elimination.

Tags

CCSS.HSA.REI.C.6

CCSS.HSA.REI.C.5