Defining Variables in Equations

The sum of a number k and 5 is 11.

• 5k = 11

• 5 - k =11

• 5/k = 11

• 5 + k = 11

The difference of a number x and 2 is 7.

• x - 2 = 7

• x + 2 = 7

• 2x = 7

• 2/x = 7

The space club is having some posters printed. The printer charges $250 plus $2 per poster. How can I figure out how many posters I could print for $1,000?

• 250x + 2 = 1000

• 1000 + 2x = 250

• 250 - 2x = 1000

• 2x + 250 = 1000

Three desks and a bookcase together weigh 157 pounds. The bookcase weighs 34 pounds. Which equation could help me find out how much each desk weighs?

• 34 + 3 = 157

• 34x + 3 = 157

• 3x + 34 = 157

• x + 34 = 157

A letter or symbol that represents an unknown value is called ______________.

• Variable

• Radicand

• Coefficient

• Constant

In the equation y=mx+b, what does the letter "x" represent?

• Slope

• Y-Intercept

• Independent Variable

• Dependent Variable

What variables represent the possible x- and y-coordinates of this equation?

Nadea has $600 in her savings account. She withdraws $35 per week to buy gas for her car. Which equation can be used to determine how many weeks, w, it will take for Nadea to reduce her balance to $285?

• (600 – 35)w = 285 

• 35w – 600 = 285 

• 600 – w = 285 

•  600 – 35w = 285

what is a variable

• A mathematical phrase that contains operations, numbers, and/or variables.

• the answer to a multiplication problem

• A number multiplied by a variable in an algebraic expression.

• a letter used for an unknown value

Translate: 
Four times a number plus six IS 30.

• 4 + 6 = 30

• 4x + 6 = 30

• x + 4 times 6 = 30

• 30 = 4x