Understanding Substitution in Graphing

The video tutorial demonstrates how to graph using substitution. It begins by explaining the concept of substitution, where one variable is replaced with another. The instructor sets up two equations, y = 4x - 1 and y = 2x - 5, and shows how to substitute one equation into the other. The process involves solving for the variable x and then finding the corresponding y value. The tutorial concludes with the solution, x = -2 and y = -9, and emphasizes the importance of understanding both x and y coordinates in graphing.

What is the primary concept behind the substitution method in graphing?

• Substituting one variable for another

• Replacing one equation with another

• Eliminating variables

• Graphing equations directly

When given two equations, what is the first step in the substitution method?

• Solve for y in both equations

• Graph both equations

• Choose which equation to substitute

• Add the equations together

What do you do after substituting one equation into another?

• Solve for the remaining variable

• Substitute back into the original equation

• Graph the result

• Check for errors

What is the result of substituting y = 4x - 1 into y = 2x - 5?

• 4x - 1 = 2x - 5

• y = 2x - 1

• x = 2y - 1

• y = 4x - 5

What is the next step after obtaining a multi-step equation with variables on both sides?

• Graph the equation

• Isolate the variable on one side

• Add a constant to both sides

• Substitute another variable

What is the value of x after solving the equation 2x - 1 = -5?

• x = 2

• x = 1

• x = -1

• x = -2

How do you find the y-coordinate after solving for x?

• Add x to both sides of the equation

• Substitute x into a new equation

• Graph the x value

• Use the x value in any original equation

Which equation can be used to find the y-coordinate after x = -2?

• y = x - 5

• y = 4x - 1

• y = 2x + 5

• y = 3x + 1

What is the y-coordinate when x = -2 in the equation y = 4x - 1?

• y = -9

• y = -7

• y = -8

• y = -10

What is the final coordinate point after solving the equations?

• (2, 9)

• (2, -9)

• (-2, -9)

• (-2, -8)