Subtraction Property of Equality
Apply the subtraction property of equality to solve one-step equations in Grade 9 Algebra. Subtract the same value from both sides to isolate the variable.
Key Concepts
Property You can subtract the same number from both sides of an equation and the statement will still be true. If $a = b$, then $a c = b c$.
Examples To solve $k + 8 = 15$, subtract 8 from both sides: $k + 8 8 = 15 8$, so $k = 7.$ To solve $ 20 = p + 10$, subtract 10 from both sides: $ 20 10 = p + 10 10$, so $ 30 = p.$.
Explanation Let's go back to our trusty balanced scale. If you take away a 3 ounce cookie from the left side, you must take a 3 ounce cookie from the right side to maintain balance. This is the key to solving equations with addition. We subtract the same number from both sides to cancel out the addition and isolate our lonely variable.
Common Questions
What is Subtraction Property of Equality in Grade 9 Algebra?
This skill covers Subtraction Property of Equality in Grade 9 Algebra. Mastering this concept builds a foundation for advanced algebra topics.
How do you approach Subtraction Property of Equality problems step by step?
Practice Subtraction Property of Equality with step-by-step examples. Use this method consistently to avoid common errors.
What is a common mistake when studying Subtraction Property of Equality?
Mastering Subtraction Property of Equality builds a strong algebra foundation. Always check your work by substituting back into the original problem.