Adding and Subtracting Rational Expressions

What definition best defines an expression?

• Can have numbers (coefficients & constants)

• Can have operators ((+,-, x, ÷)

• Can have numbers (coefficients & constants), variables, operators (+,-, x, ÷), and does not have an equal sign.

• Can have numbers (coefficients & constants), variables, operators (+,-, x, ÷), and does have an equal sign.

Which definition best defines an equation?

• Includes an equal sign (=).

• Does not include an equal sign (=)

• Can have two terms being compared to one another; it can determine whether two terms are equivalent.

• Can have two expressions being compared to one another; it can determine whether two expressions are equivalent; it includes the equal sign (=).

Choose all choices that are expressions.

• 4x+3

• (3n-7n)-16+12

• 5x+29=84

• 10s+4s-8s

Choose all choices that are equations

• 8w+3w-1=(13s-2s)-1

• 15s+(-27)

• -12x=3+9x

• 3/4w+1/2w

What is the main difference between expressions and equations?

• Equations use an equal sign (=) to separate and determine whether two expressions are equivalent and expressions do not.

• Equations have coefficients and variables and expressions do not.

• Equations can be simplified and expressions can not.

• Expressions only contain numbers and operators (+,-,x,÷) and equations do not.

What is the commutative property?

• "Changing the order does not change the result" (e.g. a + b = b +a)

• "PEMDAS"

• "Multiplying a number by a group of numbers added together" (e.g. a(b+c) = ab + ac)

Simplify the following expression.

8s+4s+5s

• 4s

• 10s

• 17s

• 32s

Simplify the following expression.

6w + (-5w)

• w

• -w

• 11w

• -11w

Simplify the following expression.

11.2b + (-13.7b)

• 1.5b

• 2.5b

• -1.5b

• -2.5b

Simplify the following expression.

(52 - 23v) + 9 + 4v

• 32v

• 79v

• 32v+9

• 79v+9