Solving for Unknown Variables

Solve for x: 7x + 7 = 21

• x = 7

• x = 4

• x = 3

• x = 2

Solve for k.... 31 - 3k = 10

• k = 10

• k = -10

• k = -7

• k = 7

What is a variable?

• It's a number equation.

• A letter representing an unknown number in an equation.

• The symbols in an equation that aren't letters or numbers.

• Any equation with an equals sign.

In the equation 2x + 3y = 19, what is/are the variable(s)? Choose the best answer.

• x

• y

• =

• Both x and y are variables

What branch of mathematics deals with equations with variables?

• Algebra

• Geometry

• Calculus

• Physics

How would you solve the equation 4x = 100?

• Divide 100 by 4

• Subtract 4 from 100

• Add 4 to 100

• Multiply 100 by 4

In the equation 2x + 3y = 19, what is the constant?

• y

• 19

• x

• 2

What is the first step in solving the equation 2y - 11 = 25

• Subtract 11 from 25

• Add 11 to 25

• Divide 25 by 2

• Multiply 25 by 2

The variables (e.g., x and y) whose values need to be found in a pair of simultaneous equations.

• Isolating Variable

• Unknown Variables

• Scientific Notations

• Descriptive Variables

An equation where one of the unknown values is isolated on one side of the equals sign.

• Rearranged Equation

• Graph Intersection

• Graph Method

• Solving Together