Adding and Subtracting Rational Expressions Explained

What is essential for adding and subtracting rational expressions?

• Finding the highest exponent

• Having a common denominator

• Subtracting the denominators

• Multiplying the numerators

Why is it important to have a common denominator when adding or subtracting rational expressions?

• To divide the expressions

• To find the highest exponent

• To multiply the expressions

• To simplify the expression

What is the common denominator in the first example?

• 2MN

• MN

• 2M^2N^2

• 2M

In the first example, what must be multiplied to the first denominator to achieve the common denominator?

• 2, M, and N

• 2 and M

• 2 and N

• M and N

How is the denominator '9 - y' rewritten to find a common denominator in the second example?

• -1(9 - y)

• y - 9

• 1 - (y - 9)

• -1(y - 9)

What is the simplified form of the second example?

• 12y / (9 - y)

• -12y / (y - 9)

• -14y + 2y / (y - 9)

• -14y / (y - 9)

What is the common denominator in the third example?

• 4

• 4X + 8

• X + 2

• 4(X + 2)

What operation is performed on the second rational expression in the third example?

• Divided by 4

• Factored out

• Simplified

• Multiplied by 4

What common mistake is highlighted in the third example?

• Adding instead of subtracting expressions

• Cancelling terms prematurely

• Incorrectly finding the common denominator

• Forgetting to factor the denominator

What should you not do after multiplying the second rational expression in the third example?

• Rewrite the common denominator

• Cancel out the 4s

• Combine like terms

• Simplify the numerator