Systems of Equations by Matrices

Solve by matrices.

4x+9y=28

-4x-y=-28

• (-7,0)

• (6,0)

• (-6,0)

• (7,0)

Solve by matrices.

7x+y=-9

-3x-y=5

• No solution

• (1,8)

• (-2,-3)

• (-1,-2)

Which method would be best for solving this system?

• Substitution

• Elimination/Matrices

What is the first step in solving a system of equations by elimination/matrices?

• Get both equations in standard form and line up the like terms.

• Get both equations in slope-intercept form.

• Get both equations equal to zero.

• Put the x terms first.

Two linear equations with the same set of variables

• system of equations

• function

• association

• correlation

Solve for x and y.
y = 2/3x - 2
y = -x + 3

• (0,3)

• (0,-3)

• (3,0)

• (-3,0)

Solve for x and y
3x + 2y = 16
7x + y = 19

• (-2,5)

• (-2,-5)

• (2,-5)

• (2,5)

How many solutions will this system have? 

• No solution

• One Solution

• I Don't Know

• Infinitely Many Solutions

Solve the system by matrices (x,y)
3x + 2y = –13
3x + 4y = 1 

• (-9,7)

• (7,-9)

• (4,-7)

• (-7,-4)

Solve using matrices.

4x + 8y = 20

-4x + 2y = -30

• (-7,1)

• (2,-5)

• (-2,5)

• (7,-1)