Solving Systems by Elimination in Grade 8 Math

The video tutorial covers solving systems of linear equations using the elimination method. It begins with an introduction to the method, followed by three detailed examples demonstrating how to eliminate variables to find solutions. The tutorial emphasizes the importance of balancing equations, combining like terms, and using substitution after elimination. It concludes with a summary of the key points and encourages students to practice explaining the method.

What is the main goal of the lesson?

• To learn how to graph linear equations

• To solve a system of linear equations by elimination

• To factor polynomials

• To understand quadratic equations

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which of the following materials is NOT mentioned as needed for the lesson?

• A calculator

• A ruler

• A highlighter

• A pen or pencil

Tags

CCSS.8.EE.C.7B

In the first example, which variable is eliminated first?

• Both x and y

• y

• x

• Neither x nor y

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the value of y in the first example after elimination?

• 15

• 10

• 5

• 20

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

In the second example, which variable is chosen to be eliminated?

• Neither x nor y

• Both x and y

• y

• x

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the value of x in the second example after elimination?

• 5

• 4

• 6

• 3

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

In the third example, what trick is used to create opposites?

• Subtracting the same number from both sides

• Multiplying both sides by -1

• Adding the same number to both sides

• Dividing both sides by 2

Tags

CCSS.6.EE.B.7

What is the value of x in the third example after elimination?

• -2

• 0

• 2

• 4

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the final ordered pair solution in the third example?

• (0, -2)

• (-2, 0)

• (0, 2)

• (2, 0)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the most important part to remember when solving systems of equations?

• The substitution method

• The elimination method

• The graphing method

• The ordered pair solution

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6