An equation is . any expression that includes a variable

a comparison between two expressions that have the same value

a variable

any combination of values, variables, and operations

A variable is .
a number

an amount that can change during the problem

a quantity expressed by a number

a placeholder for an unknown amount

A formula is an equation that .
has no terms

has no variables

expresses an important relationship

has no values

Which of the following word problems would use the distance traveled (d = rt) formula?
John has 5 gallons of gas in the tank. If his car will go 15 miles for each gallon of gas, can John travel 70 miles on the gas in his tank?

John and his dad are traveling to New York. If they drive for 4 hours at 70 miles per hour, how far did they travel?

John is filling his gas tank. If he puts 12 gallons in at $3.50 per gallon, how much did he spend?

John marks a board into three sections. If the total length is 8 feet, and the sections are equal, what is the length of each section?

5. John washes a car and a truck. He is paid $10 for the car and a total of $25 for both vehicles. If x is the amount he was paid for washing the truck, which equation correctly reflects the situation?
$25 + x = $10

$10 + $25 = x

$10 + x = $25

x + $25 = $10