Solving Systems of Linear Equations by Substitution

The video tutorial explains how to solve systems of linear equations using the substitution method. It begins with an introduction to the concept, followed by examples of substituting numbers and expressions into equations. The tutorial progresses to more complex examples, including substituting multiple terms and solving systems in standard form. Throughout, the importance of checking solutions is emphasized.

What is the first step in solving systems of linear equations by substitution?

• Checking the solution

• Rewriting the equations in standard form

• Substituting a value into one of the equations

• Graphing the equations

In the substitution method, what can you replace a variable with?

• A number or an expression

• Only another variable

• A graph

• Only a number

What is the solution to the system where 3x + y = 15 and y = 3?

• (5, 2)

• (3, 4)

• (2, 5)

• (4, 3)

In the example where J = 2K, what is the value of K if 2K + 3K = 5?

• 3

• 1

• 0

• 2

When substituting an expression, what should you remember to use?

• Brackets

• Parentheses

• Commas

• Semicolons

What is the solution to the system where 6M - N = 5 and N = M + 5?

• (8, 3)

• (3, 8)

• (7, 2)

• (2, 7)

What should you do after finding the values of the variables in a system of equations?

• Check the solution in both original equations

• Graph the solution

• Solve another system

• Rewrite the equations

In the final example, what is the first step to solve the system where X - 3Y = 9?

• Multiply both sides by 3

• Divide both sides by 3

• Subtract 3Y from both sides

• Add 3Y to both sides

What is the value of Y in the system where X - 3Y = 9 and 6X - 5Y = 2?

• -4

• 4

• -3

• 3

What is the final solution to the system where X - 3Y = 9 and 6X - 5Y = 2?

• (4, 3)

• (-4, -3)

• (3, 4)

• (-3, -4)