Unit 5 Review

What are the three main methods for solving systems of equations?

• substitution

• elimination

• graphing

• plug in zero to both variables

• plug in zero to one variable at a time

when using the method of elimination we need to...

• plug in zero to one variable at a time

• make the coefficients of one variable the same with opposite signs

• replace what one variable is equal to into the other equation

• convert to slope intercept form

when using the method of substitution we need to...

• plug in zero to one variable at a time

• make the coefficients of one variable the same with opposite signs

• replace what one variable is equal to into the other equation

• convert to slope intercept form

what is the variable that willl be "eliminated"?

5x - 4y = 11

5x + 4y = -14

• x variable

• y variables

• both variables

Solve by elimination:
4x+9y=28
-4x-y=-28

• (-7,0)
• (6,0)
• (-6,0)
• (7,0)

What would be the first step in finding the solution using elimination?

2x + 2y = -2

3x - 2y = 12

• you cannot solve this using eliminiation

• cross out the 2x and 3x

• cross out the 2y and -2y

• change to slope intercept form and graph

solve the system of equation using elimination

x - 2y = -19

5x + 2y = 1

• (3, -8)

• (-3, 11)

• (1, 0)

• (-3,8)

What is the solution to the system?

• (0, 3)

• (1, -1)

• (-3, 1)

• (1, 3)

Solve the system:

2x + 3y = -2

3x - 2y = 23

• (5, -4)

• (-4, 5)

• (-5, 4)

• infinite solutions

Solve by elimination:

4x + 8y = 20

−4x + 2y = −30

• (-1, 7)

• (-7, 1)

• (7, -1)

• (1, -7)