Solving Equations with Two Variables

This lesson covers solving equations with two variables, focusing on finding solutions and verifying ordered pairs using substitution. It includes examples of solving equations and story problems, and explores how changes in variables affect the outcome of equations.

Which ordered pair satisfies the equation X + Y = 12?

• (7, 6)

• (9, 3)

• (10, 2)

• (8, 5)

Is the point (-3, 2) a solution for the equation Y = 2X + 8?

• Cannot determine

• Yes

• No

• Needs more information

What is the result of substituting X = 5 and Y = 10 in the equation Y = 3X - 1?

• Irrelevant

• Uncertain

• False

• True

If X = -2, what is Y in the equation Y = 3X - 1?

• -7

• -6

• -5

• -10

What does X equal if Y = 3X - 2 and we know X must be 2?

• 5

• 3

• 4

• 2

In the equation 3X = 15, what is the value of X?

• 45

• 15

• 5

• 3

How much has a person saved after 12 weeks if she saves $4 per week starting with $38?

• $94

• $92

• $90

• $86

What does the total amount saved become if the saving period is extended by one week to 13 weeks?

• $86

• $90

• $92

• $94

By how much does Y increase for every unit increase in X in the equation Y = 4X + 38?

• $4

• $2

• $3

• $5

What is the new value of Y when X increases from 12 to 13 in the equation Y = 4X + 38?

• 90

• 88

• 86

• 92